Thin-film magnetic head and method of manufacturing same and thin-film magnetic head sub-structure and method of manufacturing same

ABSTRACT

An object of the invention is to provide thin-film magnetic heads that meet specifications required by the customer in a short time and to improve yields of thin-film magnetic heads. In a thin-film magnetic head sub-structure of the invention, a bottom shield layer and a first portion of a top shield layer are placed in one plane, being insulated from each other. Portions of conductive layers to be connected to an MR element are placed in grooves formed between the bottom shield layer and the first portion of the top shield layer, being insulated by an insulating film from the bottom shield layer and the first portion. A thin-film coil is placed on a first portion of the top shield layer, an insulating layer being placed between the coil and the first portion. A thin-film magnetic head is completed by adding the MR element, a second portion of the top shield layer placed on top of the MR element, a recording gap layer, a top pole layer and so on.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a thin-film magnetic head having atleast a magnetoresistive element for reading and a method ofmanufacturing such a magnetic head, and to a thin-film magnetic headmaterial used for producing a composite thin-film magnetic head having amagnetoresistive element and an induction-type magnetic transducer and amethod of manufacturing such a thin-film magnetic head material.

2. Description of the Related Art

Performance improvements in thin-film magnetic heads have been soughtwith an increase in surface recording density of a hard disk drive. Acomposite thin-film magnetic head has been widely used which is made ofa layered structure including a recording head having an inductionmagnetic transducer for writing and a reproducing head having amagnetoresistive (MR) element for reading. MR elements include ananisotropic magnetoresistive (AMR) element that utilizes the AMR effectand a giant magnetoresistive (GMR) element that utilizes the GMR effect.A reproducing head using an AMR element is called AMR head or simply MRhead. A reproducing head using a GMR element is called GMR head. An AMRhead is used as a reproducing head whose surface recording density ismore than 1 gigabit per square inch. A GMR head is used as a reproducinghead whose surface recording density is more than 3 gigabits per squareinch.

An AMR head comprises an AMR film having the AMR effect. In place of theAMR film a GMR head comprises a GMR film having the GMR effect. Theconfiguration of the GMR head is similar to that of the AMR head.However, the GMR film exhibits a greater change in resistance under aspecific external magnetic field compared to the AMR film. As a result,the reproducing output of the GMR head is about three to five times asgreat as that of the AMR head.

The MR film may be changed in order to improve the performance of areproducing head. In general, an AMR film is made of a magneticsubstance that exhibits the MR effect and has a single-layer structure.In contrast, many of GMR films have a multilayer structure consisting ofa plurality of films. There are several types of mechanisms of producingthe GMR effect. The layer structure of a GMR film depends on themechanism. GMR films include a superlattice GMR film, a granular film, aspin valve film and so on. The spin valve film is most efficient sincethe film has a relatively simple structure, exhibits a great change inresistance in a low magnetic field, and suitable for mass production.The performance of the reproducing head is thus easily improved byreplacing the AMR film with a GMR film and the like with an excellentmagnetoresistive sensitivity.

Besides selection of a material as described above, the pattern widthsuch as the MR height, in particular, determines the performance of areproducing head. The MR height is the length (height) between the endof the MR element closer to the air bearing surface (medium facingsurface) and the other end. The MR height is basically controlled by anamount of lapping when the air bearing surface is processed.

Many of reproducing heads have a structure in which the MR element iselectrically and magnetically shielded by a magnetic material.

Referring to FIG. 91 to FIG. 100, an example of a manufacturing methodof a composite thin-film magnetic head will now be described as anexample of a manufacturing method of a related-art thin-film magnetichead. FIGS. 91A to FIG. 98A are cross sections orthogonal to the airbearing surface. FIGS. 91B to FIG. 98B are cross sections parallel tothe air bearing surface of the pole portion.

According to the manufacturing method, as shown in FIGS. 91A and 91B, aninsulating layer 1102 made of alumina (Al₂O₃), for example, of about 5to 10 μm in thickness is deposited on a substrate 1101 made of aluminumoxide and titanium carbide (Al₂O₃-TiC), for example. On the insulatinglayer 1102 a bottom shield layer 1103 made of a magnetic material of 2to 3 μm in thickness is formed for a reproducing head.

Next, as shown in FIGS. 92A and 92B, on the bottom shield layer 1103alumina or aluminum nitride, for example, of 50 to 100 nm in thicknessis deposited through sputtering to form a bottom shield gap film 1104 asan insulating layer. On the bottom shield gap film 1104 an MR film oftens of nanometers in thickness is formed for making an MR element 1105for reproduction. Next, on the MR film a photoresist pattern 1106 isselectively formed where the MR element 1105 is to be formed. Thephotoresist pattern 1106 takes a shape that easily allows lift-off, suchas a shape having a T-shaped cross section. Next, with the photoresistpattern 1106 as a mask, the MR film is etched through ion milling toform the MR element 1105. The MR element 1105 may be either a GMRelement or an AMR element.

Next, as shown in FIGS. 93A and 93B, on the bottom shield gap film 1104a pair of first conductive layers 1107 whose thickness is tens ofnanometers are formed, using the photoresist pattern 1106 as a mask. Thefirst conductive layers 1107 are electrically connected to the MRelement 1105. The first conductive layers 1107 may have a multilayerstructure including TiW, CoPt, TiW, and Ta, for example. Next, as shownin FIGS. 94A and 94B, the photoresist pattern 1106 is lifted off.Although not shown in FIGS. 94A and 94B, a pair of second conductivelayers whose thickness is 50 to 100 nm are formed in a specific pattern.The second conductive layers are electrically connected to the firstconductive layers 1107. The second conductive layers may be made ofcopper (Cu), for example. The first conductive layers 1107 and thesecond conductive layers make up leads electrically connected to the MRelement 1105.

Next, as shown in FIG. 95A and FIG. 95B, a top shield gap film 1108 of50 to 150 nm in thickness is formed as an insulating layer on the bottomshield gap film 1104 and the MR film 1105. The MR film 1105 is embeddedin the shield gap films 1104 and 1108. Next, on the top shield gap film1108 a top shield layer-cum-bottom magnetic layer (called top shieldlayer in the following description) 1109 of about 3 μm in thickness isformed. The top shield layer 1109 is made of a magnetic material andused for both a reproducing head and a recording head.

Next, as shown in FIG. 96A and FIG. 96B, on the top shield layer 1109, arecording gap layer 1110 made of an insulating film such as an aluminafilm is formed whose thickness is about 0.2 to 0.3 μm. On the recordinggap layer 1110 a photoresist layer 1111 for determining the throatheight is formed into a specific pattern whose thickness is about 1.0 to2.0 μm. Next, on the photoresist layer 1111 a thin-film coil 1112 of afirst layer is made for the induction-type recording head. The thicknessof the thin-film coil 1112 is 3 μm. Next, a photoresist layer 1113 isformed into a specific pattern on the photoresist layer 1111 and thecoil 1112. On the photoresist layer 1113 a thin-film coil 1114 of asecond layer is then formed into a thickness of 3 μm. Next, aphotoresist layer 1115 is formed into a specific pattern on thephotoresist layer 1113 and the coil 1114.

Next, as shown in FIG. 97A and FIG. 97B, the recording gap layer 1110 ispartially etched in a portion behind the coils 1112 and 1114 (the rightside of FIG. 97A) to form a magnetic path. A top pole layer 1116 ofabout 3 μm in thickness is then formed on the recording gap layer 1110and the photoresist layers 1111, 1113 and 1115. The top pole layer 1116is made of a magnetic material for the recording head such as Permalloy(NiFe) or FeN as a high saturation flux density material. The top polelayer 1116 comes to contact with the top shield layer (bottom polelayer) 1109 and is magnetically coupled to the top shield layer 1109 ina portion behind the coils 1112 and 1114.

As shown in FIG. 98A and FIG. 98B, the recording gap layer 1110 and thetop shield layer (bottom pole layer) 1109 are etched through ionmilling, using the top pole layer 1116 as a mask. Next, an overcoatlayer 1117 of alumina, for example, having a thickness of 20 to 30 μm isformed to cover the top pole layer 1116. Finally, machine processing ofthe slider is performed to form the air bearing surface of the recordinghead and the reproducing head. The thin-film magnetic head is thuscompleted. As shown in FIG. 98B, the structure is called trim structurewherein the sidewalls of the top pole layer 1116, the recording gaplayer 1110, and part of the top shield layer (bottom pole layer) 1109are formed vertically in a self-aligned manner. The trim structuresuppresses an increase in the effective track width due to expansion ofthe magnetic flux generated during writing in a narrow track.

FIG. 99 is a top view of the thin-film magnetic head manufactured asdescribed above. The overcoat layer 1117 is omitted in FIG. 99. FIG. 100is a top view wherein the MR element 1105, the first conductive layer1107 and the second conductive layer 1118 are formed on the bottomshield gap film 1104. FIG. 91A to FIG. 98A are cross sections takenalong line 98A-98A of FIG. 99. FIG. 91B to FIG. 98B are cross sectionstaken along line 98B—98B of FIG. 99.

As shown in FIG. 99 and FIG. 100, the related-art thin-film magnetichead has the structure wherein the conductive layers 1107 and 1118connected to the MR element 1105 are inserted in a wide region betweenthe bottom shield layer 1103 and the top shield layer 1109 for shieldingthe MR element 1105. The very thin bottom shield gap film 1104 and topshield gap film 1108 are each placed between the shield layer 1103 andthe conductive layers 1107 and 1118 and between the shield layer 1109and the conductive layers 1107 and 1118, respectively. High insulationproperty is therefore required for the shield gap films 1104 and 1108.The yields of the thin-film magnetic heads thus greatly depend on theinsulation property.

With improvements in performance of the recording head, a problem ofthermal asperity comes up. Thermal asperity is a reduction inreproducing characteristic due to self-heating of the reproducing headduring reproduction. To overcome thermal asperity, a material with highcooling efficiency is required for the bottom shield layer 1103 and theshield gap films 1104 and 1108 in the related-art. Therefore, the bottomshield layer 1103 is made of a magnetic material such as Permalloy orSendust in the related-art. The shield gap films 1104 and 1108 are madeof a material such as alumina, through sputtering, into a thickness of100 to 150 nm, for example. The shield gap films 1104 and 1108 thusmagnetically and electrically isolate the shield layers 1103 and 1109from the MR element 1105 and the conductive layers 1107 and 1118.

It is inevitable that thermal asperity should be overcome in order toimprove the performance of the reproducing head. Recently, the thicknessof the shield gap films 1104 and 1108 has been reduced to as thin as 50to 100 nm, for example. The cooling efficiency of the MR element 1105 isthereby improved so as to overcome thermal asperity.

However, since the shield gap films 1104 and 1108 are formed throughsputtering, faults may result in the magnetic and electrical insulationthat isolates the shield layers 1103 and 1109 from the MR element 1105and the conductive layers 1107 and 1118, due to particles or pinholes inthe films. Such faults more often result if the shield gap films 1104and 1108 are thinner.

In order to improve the output characteristic of the reproducing head,it is preferred that the wiring resistance of the conductive layerconnected to the MR element is as low as possible so that a minutechange in the output signal corresponding to a minute change inresistance of the MR element can be detected. Therefore, the area of theconductive layer 1118 is often designed to be large in the related-art.However, the areas of the portions of the conductive layers 1118 thatface the shield gap films 1104 and 1108 are made large, as a result. Ifthe shield gap films 1104 and 1108 are thin as described above, magneticand electrical insulation faults may more often result between theconductive layers 1118 and each of the shield layers 1103 and 1109.

As described above, it is preferred that the wiring resistance of theconductive layers connected to the MR element is low to improve theoutput characteristic of the reproducing head. However, there is a limitto reducing the wiring resistance of the conductive layers since theconductive layers 1107 and 1118 as thin as 50 to 100 nm are insertedbetween the shield layers 1103 and 1109 in the related-art thin-filmmagnetic head.

Since a narrow track width is required for the thin-magnetic head, aminute-size MR element is required. For the GMR head, in particular, itis required to precisely detect the output signal of the minute MRelement. It is therefore required to reduce noises caused by internalfactors such as the coils of the induction-type recording head orexternal factors such as the motor of the hard disk drive. However, theconductive layers 1118 carry noises in the related-art thin-filmmagnetic head. Such noises may reduce the performance of the reproducinghead.

In Japanese Patent Application Laid-open Hei 9-312006 (1997) a techniqueis disclosed for reducing the electric resistance of the lead andpreventing insulation faults between the lead and the top shield. Thelength of the bottom shield is made shorter than the top shield in thedirection of drawing out the lead connected to the MR element frombetween the top and bottom shields. The thickness of the portion of thelead between the top and bottom shields is made thin. The portion of thelead off the bottom shield is made thick and to protrude downward.

In the technique, however, the lead is hardly shielded by the bottomshield. As a result, magnetic flux from the coil is easily received inthe GMR head that requires a high output. The lead therefore tends tocarry noises.

A technique disclosed in Japanese Patent Application Laid-open Sho60-93613 (1985) is that a spacer layer is formed on an MR element andcontact holes are made in the spacer layer to expose part of the MRelement. A shield film and a conductive film (lead) are then formed atthe same time, and the conductive film is connected to the MR elementthrough the contact holes.

The technique prevents insulation faults between the conductive film andthe shield film. However, the conductive film tends to carry noisessince the conductive film is not shielded by the shield film.

OBJECTS AND SUMMARY OF THE INVENTION

It is a first object of the invention to provide a thin-film magnetichead and a method of manufacturing the same and a thin-film magnetichead material and a method of manufacturing the same for improving theinsulation property between the shield layer and the conductive layerconnected to the magnetoresistive element without increasing thethickness of the insulating layer between the shield layer and themagnetoresistive element.

It is a second object of the invention to provide a thin-film magnetichead and a method of manufacturing the same and a thin-film magnetichead material and a method of manufacturing the same for reducing thewiring resistance of the conductive layer connected to themagnetoresistive element.

It is a third object of the invention to provide a thin-film magnetichead and a method of manufacturing the same and a thin-film magnetichead material and a method of manufacturing the same for reducing theeffect of noises on the conductive layer connected to themagnetoresistive element.

A first thin-film magnetic head of the invention comprises: amagnetoresistive element; a first shield layer and a second shield layerfor shielding the magnetoresistive element, wherein portions of thefirst shield layer and the second shield layer facing a recording mediumare opposed to each other with the magnetoresistive element; a firstinsulating layer provided between the magnetoresistive element and thefirst shield layer and a second insulating layer provided between themagnetoresistive element and the second shield layer; a conductive layerconnected to the magnetoresistive element; and a groove in which atleast part of the conductive layer is placed, the groove being formed ineither the first shield layer or the second shield layer, or between thefirst and second shield layers. The at least part of the conductivelayer is placed in the groove, being insulated from the shield layerhaving the groove or the shield layers facing the groove.

In the first thin-film magnetic head of the invention, the at least partof the conductive layer connected to the magnetoresistive element isplaced in the groove formed in either the first shield layer or thesecond shield layer, or between the first and second shield layers,being insulated from the shield layer having the groove or the shieldlayers facing the groove. As a result, the insulation property isimproved between the conductive layer and the shield layer withoutincreasing the thickness of the insulating layer between themagnetoresistive element and the shield layer.

In the first thin-film magnetic head of the invention, the groove may beformed in the first shield layer. In this case the followingconfigurations (1) to (3) are possible. (1) The at least part of theconductive layer placed in the groove is made of a material the same asa material the first shield layer is made of. (2) The thin-film magnetichead further comprises a seed layer electrically connected to the firstshield layer, formed in a region greater than a region where the firstshield layer is formed, and used for forming the first shield layer. (3)The first shield layer is divided into a portion facing themagnetoresistive element and a portion not facing the magnetoresistiveelement.

The first thin-film magnetic head of the invention may further comprisean insulating film placed in the groove. The insulating film insulatesthe at least part of the conductive layer from the shield layer havingthe groove or the shield layers facing the groove.

The first thin-film magnetic head of the invention may further comprisean induction-type magnetic transducer having two magnetic layersmagnetically coupled to each other and a thin-film coil placed betweenthe two magnetic layers. Parts of sides of the two magnetic layersfacing a recording medium include magnetic pole portions opposed to eachother with a gap layer in between. The magnetic layers are each made upof at least one layer. In this case the following configurations (1) to(3) are possible. (1) One of the first and second shield layersfunctions as one of the two magnetic layers as well. (2) At least partof the groove is placed around a region facing the two magnetic layersand the thin-film coil of the induction-type magnetic transducer. (3) Atleast part of the groove is placed to pass through a region facing thetwo magnetic layers and the thin-film coil of the induction-typemagnetic transducer.

The first thin-film magnetic head of the invention may further comprisea shield layer for shielding the at least part of the conductive layer.

In the first thin-film magnetic head of the invention, the second shieldlayer may include a first portion at least part of which is placed inthe same plane as the first shield layer and a second portion connectedto the first portion, the second portion being opposed to the firstshield layer with the magnetoresistive element in between. The groove isformed between the first shield layer and the first portion of thesecond shield layer.

With the above configuration the thin-film magnetic head may furthercomprise an induction-type magnetic transducer having two magneticlayers magnetically coupled to each other and a thin-film coil placedbetween the two magnetic layers. Parts of sides of the two magneticlayers facing a recording medium include magnetic pole portions opposedto each other with a gap layer in between. The magnetic layers are eachmade up of at least one layer. In this case the following configurations(1) and (2) are possible. (1) At least part of the thin-film coil isplaced on a side of the second portion of the second shield layer in adirection parallel to surfaces of the second portion. (2) The thin-filmmagnetic head further comprises a base body having a concave potion. Atleast part of the first shield layer is placed in a portion other thanthe concave portion on the surface of the base body where the concaveportion is formed. Part of the first portion of the second shield layeris placed in a portion other than the concave portion on the surface ofthe base body where the concave portion is formed. The remaining part ofthe first portion of the second shield layer is placed along the innersurface of the concave portion. At least part of the thin-film coil isplaced in the concave portion.

A second or third thin-film magnetic head of the invention comprises: amagnetoresistive element; a first shield layer and a second shield layerfor shielding the magnetoresistive element, wherein portions of thefirst shield layer and the second shield layer facing a recording mediumare opposed to each other with the magnetoresistive element in between;a first insulating layer provided between the magnetoresistive elementand the first shield layer and a second insulating layer providedbetween the magnetoresistive element and the second shield layer; and aconductive layer connected to the magnetoresistive element. The firstshield layer and at least part of the conductive layer are made of onematerial, placed in one plane and insulated from each other.

The second thin-film magnetic head of the invention further comprises ashield layer for shielding the at least part of the conductive layer.

The third thin-film magnetic head of the invention further comprises aseed layer electrically connected to the at least part of the conductivelayer, formed in a region greater than a region where the at least partof the conductive layer is formed, and used for forming the at leastpart of the conductive layer.

In the second or third thin-film magnetic head of the invention, thefirst shield layer and at least part of the conductive layer are made ofone material, placed in one plane and insulated from each other. As aresult, the insulation property is improved between the conductive layerand the shield layer without increasing the thickness of the insulatinglayer between the magnetoresistive element and the shield layer.

The third thin-film magnetic head of the invention may further comprisea shield layer for shielding the at least part of the conductive layer.

A first method of the invention is provided for manufacturing athin-film magnetic head comprising: a magnetoresistive element; a firstshield layer and a second shield layer for shielding themagnetoresistive element, wherein portions of the first shield layer andthe second shield layer facing a recording medium are opposed to eachother with the magnetoresistive element in between; a first insulatinglayer provided between the magnetoresistive element and the first shieldlayer and a second insulating layer provided between themagnetoresistive element and the second shield layer; and a conductivelayer connected to the magnetoresistive element.

The first method of manufacturing a thin-film magnetic head of theinvention includes the steps of: forming the first shield layer; formingthe first insulating film on the first shield layer; forming themagnetoresistive element on the first insulating layer; forming thesecond insulating layer on the magnetoresistive element and the firstinsulating layer; and forming the second shield layer so that theportion of the second shield layer facing the recording medium isopposed to the first shield layer with the first insulating layer, themagnetoresistive element and the second insulating layer in between. Agroove in which at least part of the conductive layer is placed isformed in either the first shield layer or the second shield layer, orbetween the first and second shield layers in at least one of the stepof forming the first shield layer and the step of forming the secondshield layer. The method further includes the step of forming theconductive layer so that at least part of the conductive layer is placedin the groove, being insulated from the shield layer having the grooveor the shield layers facing the groove.

In the first method of manufacturing a thin-film magnetic head of theinvention, the at least part of the conductive layer connected to themagnetoresistive element is placed in the groove formed in either thefirst shield layer or the second shield layer, or between the first andsecond shield layers, being insulated from the shield layer having thegroove or the shield layers facing the groove. As a result, theinsulation property is improved between the conductive layer and theshield layer without increasing the thickness of the insulating layerbetween the magnetoresistive element and the shield layer.

In the first method, the groove may be formed in the first shield layer.In this case the following configurations (1) to (5) are possible. (1)The at least part of the conductive layer placed in the groove is formedat the same time as the first shield layer and made of the same materialas the first shield layer in the step of forming the first shield layerand the step of forming the conductive layer. (2) The method furthercomprises the step of forming a seed layer electrically connected to thefirst shield layer, formed in a region greater than a region where thefirst shield layer is formed, and used for forming the first shieldlayer. (3) The first shield layer is divided into a portion facing themagnetoresistive element and a portion not facing the magnetoresistiveelement. (4) The first shield layer is formed by plating. (5) The atleast part of the conductive layer is formed by plating.

As stated above, if the at least part of the conductive layer placed inthe groove is formed at the same time as the first shield layer and madeof the same material as the first shield layer in the step of formingthe first shield layer and the step of forming the conductive layer, thefirst shield layer and the at least part of the conductive layer may beformed by plating or formed by depositing films through sputtering andselectively etching the films through dry etching.

The first method may further include the step of forming an insulatingfilm placed in the groove. The insulating film insulates the at leastpart of the conductive layer from the shield layer having the groove orthe shield layers facing the groove.

The first method may further include the step of forming aninduction-type magnetic transducer having two magnetic layersmagnetically coupled to each other and a thin-film coil placed betweenthe two magnetic layers. Parts of sides of the two magnetic layersfacing a recording medium include magnetic pole portions opposed to eachother with a gap layer in between. The magnetic layers are each made upof at least one layer. In this case the following configurations (1) to(4) are possible. (1) One of the first and second shield layersfunctions as one of the two magnetic layers as well. (2) At least partof the groove is placed around a region facing the two magnetic layersand the thin-film coil of the induction-type magnetic transducer. (3) Atleast part of the groove is placed to pass through a region facing thetwo magnetic layers and the thin-film coil of the induction-typemagnetic transducer. (4) The method further includes the step of forminga shield layer for shielding at least part of the conductive layer atthe same time as forming the one of the magnetic layers of theinduction-type magnetic transducer.

The first method may further include the step of forming a shield layerfor shielding at least part of the conductive layer.

In the first method, for example, a first portion and a second portionof the second shield layer are formed in the step of forming the secondshield layer, at least part of the first portion being placed in thesame plane as the first shield layer so that the groove is formedbetween the first shield layer and the first portion, the second portionbeing connected to the first portion and being opposed to the firstshield layer with the magnetoresistive element in between. In this casethe following configurations (1) to (4) are possible. (1) The firstportion of the second shield layer is formed at the same time as thefirst shield layer and made of the same material as the first shieldlayer in the step of forming the first shield layer and the step offorming the second shield layer. (2) The method further includes thestep of forming an induction-type magnetic transducer having twomagnetic layers magnetically coupled to each other and a thin-film coilplaced between the two magnetic layers. Parts of sides of the twomagnetic layers facing a recording medium include magnetic pole portionsopposed to each other with a gap layer in between. The magnetic layersare each made up of at least one layer. (3) The first shield layer andthe first portion of the second shield layer placed in the one plane areformed by plating. (4) The at least part of the conductive layer isformed by plating.

If the method includes the step of forming the induction-type magnetictransducer as stated above, at least part of the thin-film coil may beplaced on a side of the second portion of the second shield layer in adirection parallel to surfaces of the second portion.

If the method includes the step of forming the induction-type magnetictransducer as stated above, the at least part of the conductive layerand at least part of the thin-film coil may be formed by plating, forexample, at the same time in the step of forming the conductive layerand the step of forming the induction-type magnetic transducer.

If the method includes the step of forming the induction-type magnetictransducer as stated above, the thin-film magnetic head may furthercomprise a base body having a concave portion. At least part of thefirst shield layer is placed in a portion other than the concave portionon the surface of the base body where the concave portion is formed.Part of the first portion of the second shield layer is placed in aportion other than the concave portion on the surface of the base bodywhere the concave portion is formed. The remaining part of the firstportion of the second shield layer is placed along the inner surface ofthe concave portion. At least part of the thin-film coil is placed inthe concave portion. In this case the following configurations (1) and(2) are possible. (1) The step of forming the induction-type magnetictransducer includes the steps of: forming the at least part of thethin-film coil in the concave portion; forming an insulating portion tocover the at least part of the thin-film coil in the concave portion;and flattening the surfaces of the insulating portion, the first shieldlayer and the first portion of the second shield layer so that thesurfaces are brought to one plane. (2) The step of forming theinduction-type magnetic transducer includes the steps of: forming partof the thin-film coil in the concave portion; forming a first insulatingportion to cover the part of the thin-film coil in the concave portion;flattening the surfaces of the first insulating portion, the firstshield layer and the first portion of the second shield layer so thatthe surfaces are brought to one plane; forming the remaining part of thethin-film coil on the first insulating portion; forming a secondinsulating portion to cover the remaining part of the thin-film coil;and flattening the surfaces of the second insulating portion and thesecond portion of the second shield layer so that the surfaces arebrought to one plane.

A second or third method of the invention is provided for manufacturinga thin-film magnetic head comprising: a magnetoresistive element; afirst shield layer and a second shield layer for shielding themagnetoresistive element, wherein portions of the first shield layer andthe second shield layer facing a recording medium are opposed to eachother with the magnetoresistive element in between; a first insulatinglayer provided between the magnetoresistive element and the first shieldlayer and a second insulating layer provided between themagnetoresistive element and the second shield layer; and a conductivelayer connected to the magnetoresistive element.

The second method of the invention includes the steps of: forming thefirst shield layer; forming the first insulating film on the firstshield layer; forming the magnetoresistive element on the firstinsulating film; forming the second insulating film on themagnetoresistive element and the first insulating film; and forming thesecond shield layer so that the portion of the second shield layerfacing the recording medium is opposed to the first shield layer withthe first insulating layer, the magnetoresistive element and the secondinsulating layer in between. The first shield layer and at least part ofthe conductive layer are made of one material, placed in one plane andinsulated from each other in the step of forming the first shield layerand the step of forming the conductive layer. The method furtherincludes the step of forming a shield layer for shielding at least partof the conductive layer.

The third method of the invention includes the steps of: forming thefirst shield layer; forming the first insulating layer on the firstshield layer; forming the magnetoresistive element on the firstinsulating layer; forming the second insulating layer on themagnetoresistive element and the first insulating layer; and forming thesecond shield layer so that the portion of the second shield layerfacing the recording medium is opposed to the first shield layer withthe first insulating layer, the magnetoresistive element and the secondinsulating layer in between. The first shield layer and at least part ofthe conductive layer are made of one material, placed in one plane andinsulated from each other in the step of forming the first shield layerand the step of forming the conductive layer. The method furtherincludes the step of forming a seed layer electrically connected to atleast part of the conductive layer and used for forming the at leastpart of the conductive layer, the seed layer being formed in a regiongreater than a region where the at least part of the conductive layer isformed.

In the second or third method of the invention, the first shield layerand at least part of the conductive layer are made of one material,placed in one plane and insulated from each other. As a result, theinsulation property is improved between the conductive layer and theshield layer without increasing the thickness of the insulating layerbetween the magnetoresistive element and the shield layer.

The third method may further include the step of forming a shield layerfor shielding the at least part of the conductive layer.

A thin-film magnetic head material of the invention is used formanufacturing a thin-film magnetic head comprising: a magnetoresistiveelement; a first shield layer and a second shield layer for shieldingthe magnetoresistive element, wherein portions of the first shield layerand the second shield layer facing a recording medium are opposed toeach other with the magnetoresistive element in between; a firstinsulating layer provided between the magnetoresistive element and thefirst shield layer and a second insulating layer provided between themagnetoresistive element and the second shield layer; a conductive layerconnected to the magnetoresistive element; and an induction-typemagnetic transducer. In the magnetic head the induction-type magnetictransducer has a first magnetic layer and a second magnetic layermagnetically coupled to each other and a thin-film coil placed betweenthe two magnetic layers. Parts of sides of the two magnetic layersfacing a recording medium include magnetic pole portions opposed to eachother with a gap layer in between. The magnetic layers are each made upof at least one layer. The second shield layer includes a first portionat least part of which is placed in the same plane as the first shieldlayer and a second portion connected to the first portion, the secondportion being opposed to the first shield layer with themagnetoresistive element in between. The second shield layer functionsas the first magnetic layer as well.

The thin-film magnetic head material of the invention comprises: thefirst shield layer; the first portion of the second shield layer placedsuch that a groove in which at least part of the conductive layer isplaced is formed between the first shield layer and the first portion;the at least part of the conductive layer placed in the groove, beinginsulated from the first shield layer and the first portion of thesecond shield layer; and at least part of the thin-film coil placed toface the first portion of the second shield layer.

In the thin-film magnetic head material of the invention, at least partof the conductive layer connected to the magnetoresistive element isplaced in the groove formed between the first layer and the firstportion of the second shield layer, being insulated from the firstshield layer and the first portion. As a result, the insulation propertyis improved between the conductive layer and the shield layer withoutincreasing the thickness of the insulating layer between themagnetoresistive element and the shield layer.

The thin-film magnetic head material of the invention may furthercomprise an insulating film placed in the groove. The insulating filminsulates at least part of the conductive layer from the first shieldlayer and the first portion of the second shield layer.

The thin-film magnetic head material of the invention may furthercomprise a base body having a concave potion. At least part of the firstshield layer is placed in a portion other than the concave portion onthe surface of the base body where the concave portion is formed. Partof the first portion of the second shield layer is placed in a portionother than the concave portion on the surface of the base body where theconcave portion is formed. The remaining part of the first portion ofthe second shield layer is placed along the inner surface of the concaveportion. At least part of the thin-film coil is placed in the concaveportion.

A method of the invention is provided for manufacturing a thin-filmmagnetic head material used for manufacturing a thin-film magnetic headcomprising: a magnetoresistive element; a first shield layer and asecond shield layer for shielding the magnetoresistive element, whereinportions of the first shield layer and the second shield layer facing arecording medium are opposed to each other with the magnetoresistiveelement in between; a first insulating layer provided between themagnetoresistive element and the first shield layer and a secondinsulating layer provided between the magnetoresistive element and thesecond shield layer; a conductive layer connected to themagnetoresistive element; and an induction-type magnetic transducer. Inthe magnetic head, the induction-type magnetic transducer has a firstmagnetic layer and a second magnetic layer magnetically coupled to eachother and a thin-film coil placed between the two magnetic layers. Partsof sides of the two magnetic layers facing a recording medium includemagnetic pole portions opposed to each other with a gap layer inbetween. The magnetic layers are each made up of at least one layer. Thesecond shield layer includes a first portion at least part of which isplaced in the same plane as the first shield layer and a second portionconnected to the first portion, the second portion being opposed to thefirst shield layer with the magnetoresistive element in between. Thesecond shield layer functions as the first magnetic layer as well.

The method of manufacturing a thin-film magnetic head material of theinvention includes the steps of: forming the first shield layer; formingthe first portion of the second shield layer such that a groove in whichat least part of the conductive layer is placed is formed between thefirst shield layer and the first portion; forming the at least part ofthe conductive layer placed in the groove, being insulated from thefirst shield layer and the first portion of the second shield layer; andforming at least part of the thin-film coil on the first portion of thesecond shield layer.

In the method of manufacturing a thin-film magnetic head material of theinvention, at least part of the conductive layer connected to themagnetoresistive element is placed in the groove formed between thefirst layer and the first portion of the second shield layer, beinginsulated from the first shield layer and the first portion. As aresult, the insulation property is improved between the conductive layerand the shield layer without increasing the thickness of the insulatinglayer between the magnetoresistive element and the shield layer.

The method may further include the step of forming an insulating filmplaced in the groove, the insulating film insulating at least part ofthe conductive layer from the first shield layer and the first portionof the second shield layer.

In the method the first portion of the second shield layer may be formedat the same time as the first shield layer and made of the same materialas the first shield layer in the step of forming the first shield layerand the step of forming the first portion of the second shield layer.

In the method the first shield layer and the first portion of the secondshield layer may be formed by plating. At least part of the conductivelayer may be formed by plating.

In the method the at least part of the conductive layer and the at leastpart of the thin-film coil may be formed by plating at the same time inthe step of forming the at least part of the conductive layer and thestep of forming the at least part of the thin-film coil.

In the method the thin-film magnetic head material may comprise a basebody having a concave portion. At least part of the first shield layeris placed in a portion other than the concave portion on the surface ofthe base body where the concave portion is formed. Part of the firstportion of the second shield layer is placed in a portion other than theconcave portion on the surface of the base body where the concaveportion is formed. The remaining part of the first portion of the secondshield layer is placed along the inner surface of the concave portion.At least part of the thin-film coil is placed in the concave portion.

The method may further include the steps of: forming an insulatingportion to cover the at least part of the thin-film coil in the concaveportion; and flattening the surfaces of the insulating portion, thefirst shield layer and the first portion of the second shield layer sothat the surfaces are brought to one plane.

Other and further objects, features and advantages of the invention willappear more fully from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A and FIG. 1B are cross sections for illustrating a step in amethod of manufacturing a thin-film magnetic head of a first embodimentof the invention.

FIG. 2A and FIG. 2B are cross sections for illustrating a step thatfollows FIG. 1A and FIG. 1B.

FIG. 3A and FIG. 3B are cross sections for illustrating a step thatfollows FIG. 2A and FIG. 2B.

FIG. 4A and FIG. 4B are cross sections for illustrating a step thatfollows FIG. 3A and FIG. 3B.

FIG. 5A and FIG. 5B are cross sections for illustrating a step thatfollows FIG. 4A and FIG. 4B.

FIG. 6A and FIG. 6B are cross sections for illustrating a step thatfollows FIG. 5A and FIG. 5B.

FIG. 7A and FIG. 7B are cross sections for illustrating a step thatfollows FIG. 6A and FIG. 6B.

FIG. 8A and FIG. 8B are cross sections for illustrating a step thatfollows FIG. 7A and FIG. 7B.

FIG. 9A and FIG. 9B are cross sections for illustrating a step thatfollows FIG. 8A and FIG. 8B.

FIG. 10A and FIG. 10B are cross sections of the thin-film magnetic headof the first embodiment of the invention.

FIG. 11 is a top view of a bottom shield layer of the thin-film magnetichead of the first embodiment of the invention.

FIG. 12 is a top view of the thin-film magnetic head of the firstembodiment of the invention.

FIG. 13 is a top view of another example of the bottom shield layer ofthe thin-film magnetic head of the first embodiment of the invention.

FIG. 14 is a top view of still another example of the bottom shieldlayer of the thin-film magnetic head of the first embodiment of theinvention.

FIG. 15 is a top view of a thin-film magnetic head of a secondembodiment of the invention.

FIG. 16A and FIG. 16B are cross sections of a thin-film magnetic head ofa third embodiment of the invention.

FIG. 17A and FIG. 17B are cross sections of a thin-film magnetic head ofa fourth embodiment of the invention.

FIG. 18 is a top view of a thin-film magnetic head of a fifth embodimentof the invention.

FIG. 19 is a top view of a bottom shield layer of the thin-film magnetichead of the fifth embodiment of the invention.

FIG. 20 is a top view of conductive layers of the fifth embodiment ofthe invention.

FIG. 21 is a top view of a bottom shield layer and conductive layers ofa sixth embodiment of the invention.

FIG. 22 is a top view of the main part of a thin-film magnetic head ofthe sixth embodiment of the invention.

FIG. 23A and FIG. 23B are cross sections for illustrating a step in amethod of manufacturing a thin-film magnetic head of a seventhembodiment of the invention.

FIG. 24A and FIG. 24B are cross sections for illustrating a step thatfollows FIG. 23A and FIG. 23B.

FIG. 25A and FIG. 25B are cross sections for illustrating a step thatfollows FIG. 24A and FIG. 24B.

FIG. 26A and FIG. 26B are cross sections for illustrating a step thatfollows FIG. 25A and FIG. 25B.

FIG. 27A and FIG. 27B are cross sections for illustrating a step thatfollows FIG. 26A and FIG. 26B.

FIG. 28A and FIG. 28B are cross sections for illustrating a step thatfollows FIG. 27A and FIG. 27B.

FIG. 29A and FIG. 29B are cross sections for illustrating a step thatfollows FIG. 28A and FIG. 28B.

FIG. 30A and FIG. 30B are cross sections for illustrating a step thatfollows FIG. 29A and FIG. 29B.

FIG. 31A and FIG. 31B are cross sections of the thin-film magnetic headof the seventh embodiment of the invention.

FIG. 32 is a top view of a bottom shield layer and conductive layers ofthe thin-film magnetic head of the seventh embodiment of the invention.

FIG. 33 is a top view of the thin-film magnetic head of the seventhembodiment of the invention.

FIG. 34 is a top view of a thin-film magnetic head of an eighthembodiment of the invention.

FIG. 35A and FIG. 35B are cross sections of a thin-film magnetic head ofa ninth embodiment of the invention.

FIG. 36 is a top view of the thin-film magnetic head of the ninthembodiment of the invention.

FIG. 37A and FIG. 37B are cross sections of a thin-film magnetic head ofa tenth embodiment of the invention.

FIG. 38 is a top view of the thin-film magnetic head of the tenthembodiment of the invention.

FIG. 39 is a top view of a thin-film magnetic head of an eleventhembodiment of the invention.

FIG. 40A and FIG. 40B are cross sections of a thin-film magnetic head ofa twelfth embodiment of the invention.

FIG. 41 is a top view of the thin-film magnetic head of the twelfthembodiment of the invention.

FIG. 42 is a top view of a thin-film magnetic head of a thirteenthembodiment of the invention.

FIG. 43A and FIG. 43B are cross sections for illustrating a step in amethod of manufacturing a thin-film magnetic head of a fourteenthembodiment of the invention.

FIG. 44A and FIG. 44B are cross sections for illustrating a step thatfollows FIG. 43A and FIG. 43B.

FIG. 45A and FIG. 45B are cross sections for illustrating a step thatfollows FIG. 44A and FIG. 44B.

FIG. 46A and FIG. 46B are cross sections for illustrating a step thatfollows FIG. 45A and FIG. 45B.

FIG. 47A and FIG. 47B are cross sections for illustrating a step thatfollows FIG. 46A and FIG. 46B.

FIG. 48A and FIG. 48B are cross sections for illustrating a step thatfollows FIG. 47A and FIG. 47B.

FIG. 49A and FIG. 49B are cross sections for illustrating a step thatfollows FIG. 48A and FIG. 48B.

FIG. 50A and FIG. 50B are cross sections for illustrating a step thatfollows FIG. 49A and FIG. 49B.

FIG. 51A and FIG. 51B are cross sections of the thin-film magnetic headof the fourteenth embodiment of the invention.

FIG. 52 is a top view of the thin-film magnetic head of the fourteenthembodiment of the invention in the state in one of the manufacturingsteps.

FIG. 53 is a top view of the thin-film magnetic head of the fourteenthembodiment of the invention.

FIG. 54 is a top view of a thin-film magnetic head of a fifteenthembodiment of the invention.

FIG. 55A and FIG. 55B are cross sections for illustrating a step in amethod of manufacturing a thin-film magnetic head of a sixteenthembodiment of the invention.

FIG. 56A and FIG. 56B are cross sections for illustrating a step thatfollows FIG. 55A and FIG. 55B.

FIG. 57A and FIG. 57B are cross sections for illustrating a step thatfollows FIG. 56A and FIG. 56B.

FIG. 58A and FIG. 58B are cross sections for illustrating a step thatfollows FIG. 57A and FIG. 57B.

FIG. 59A and FIG. 59B are cross sections for illustrating a step thatfollows FIG. 58A and FIG. 58B.

FIG. 60A and FIG. 60B are cross sections of the thin-film magnetic headof the sixteenth embodiment of the invention.

FIG. 61 is a top view of the thin-film magnetic head of the sixteenthembodiment of the invention in the state in one of the manufacturingsteps.

FIG. 62 is a top view of the thin-film magnetic head of the sixteenthembodiment of the invention.

FIG. 63A and FIG. 63B are cross sections of a thin-film magnetic head ofa seventeenth embodiment of the invention.

FIG. 64A and FIG. 64B are cross sections for illustrating a step in amethod of manufacturing a thin-film magnetic head of an eighteenthembodiment of the invention.

FIG. 65A and FIG. 65B are cross sections for illustrating a step thatfollows FIG. 64A and FIG. 64B.

FIG. 66A and FIG. 66B are cross sections of the thin-film magnetic headof the eighteenth embodiment of the invention.

FIG. 67 is a top view of the thin-film magnetic head of the eighteenthembodiment of the invention in the state in one of the manufacturingsteps.

FIG. 68 is a top view of the thin-film magnetic head of the eighteenthembodiment of the invention.

FIG. 69A and FIG. 69B are cross sections for illustrating a step in amethod of manufacturing a thin-film magnetic head of a nineteenthembodiment of the invention.

FIG. 70A and FIG. 70B are cross sections for illustrating a step thatfollows FIG. 69A and FIG. 69B.

FIG. 71A and FIG. 71B are cross sections for illustrating a step thatfollows FIG. 70A and FIG. 70B.

FIG. 72A and FIG. 72B are cross sections for illustrating a step thatfollows FIG. 71A and FIG. 71B.

FIG. 73A and FIG. 73B are cross sections for illustrating a step thatfollows FIG. 72A and FIG. 72B.

FIG. 74A and FIG. 74B are cross sections for illustrating a step thatfollows FIG. 73A and FIG. 73B.

FIG. 75A and FIG. 75B are cross sections for illustrating a step thatfollows FIG. 74A and FIG. 74B.

FIG. 76A and FIG. 76B are cross sections for illustrating a step thatfollows FIG. 75A and FIG. 75B.

FIG. 77A and FIG. 77B are cross sections for illustrating a step thatfollows FIG. 76A and FIG. 76B.

FIG. 78A and FIG. 78B are cross sections for illustrating a step thatfollows FIG. 77A and FIG. 77B.

FIG. 79A and FIG. 79B are cross sections for illustrating a step thatfollows FIG. 78A and FIG. 78B.

FIG. 80A and FIG. 80B are cross sections of the thin-film magnetic headof the nineteenth embodiment of the invention.

FIG. 81 is a top view of the thin-film magnetic head of the nineteenthembodiment of the invention in the state in one of the manufacturingsteps.

FIG. 82 is a top view of the thin-film magnetic head of the nineteenthembodiment of the invention.

FIG. 83A and FIG. 83B are cross sections of a thin-film magnetic head ofa twentieth embodiment of the invention.

FIG. 84 is a top view of a thin-film magnetic head of a twenty-firstembodiment of the invention in the state in one of the manufacturingsteps.

FIG. 85 is a top view of the thin-film magnetic head of the twenty-firstembodiment of the invention.

FIG. 86 is a top view of a thin-film magnetic head of a twenty-secondembodiment of the invention in the state in one of the manufacturingsteps.

FIG. 87A and FIG. 87B are cross sections for illustrating a step in amethod of manufacturing a thin-film magnetic head of a twenty-thirdembodiment of the invention.

FIG. 88A and FIG. 88B are cross sections of the thin-film magnetic headof the twenty-third embodiment of the invention.

FIG. 89A and FIG. 89B are cross sections of a thin-film magnetic head ofa twenty-fourth embodiment of the invention.

FIG. 90A and FIG. 90B are cross sections of a thin-film magnetic head ofa twenty-fifth embodiment of the invention.

FIG. 91A and FIG. 91B are cross sections for illustrating a step in amethod of manufacturing a thin-film magnetic head of a related art.

FIG. 92A and FIG. 92B are cross sections for illustrating a step thatfollows FIG. 91A and FIG. 91B.

FIG. 93A and FIG. 93B are cross sections for illustrating a step thatfollows FIG. 92A and FIG. 92B.

FIG. 94A and FIG. 94B are cross sections for illustrating a step thatfollows FIG. 93A and FIG. 93B.

FIG. 95A and FIG. 95B are cross sections for illustrating a step thatfollows FIG. 94A and FIG. 94B.

FIG. 96A and FIG. 96B are cross sections for illustrating a step thatfollows FIG. 95A and FIG. 95B.

FIG. 97A and FIG. 97B are cross sections for illustrating a step thatfollows FIG. 96A and FIG. 96B.

FIG. 98A and FIG. 98B are cross sections of the related-art thin-filmmagnetic head.

FIG. 99 is a top view of the related-art thin-film magnetic head.

FIG. 100 is a top view of the related-art thin-film magnetic head in thestate in one of the manufacturing steps.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiment of the invention will now be described in detailwith reference to the accompanying drawings.

[First Embodiment]

Reference is now made to FIG. 1A to FIG. 10A, FIG. 1B to FIG. 10B, andFIG. 11 to FIG. 14 to describe a composite thin-film magnetic head and amethod of manufacturing the same of a first embodiment of the invention.FIG. 1A to FIG. 10A are cross sections each orthogonal to the airbearing surface of the thin-film magnetic head. FIG. 1B to FIG. 10B arecross sections each parallel to the air bearing surface of the poleportion of the head.

In the method of the embodiment, as shown in FIG. 1A and FIG. 1B, aninsulating layer 2 made of alumina (Al₂O₃), for example, of about 5 to10 μm in thickness is deposited on a substrate 1 made of aluminum oxideand titanium carbide (Al₂O₃-TiC), for example.

Although not shown, a seed layer (electrode film) is made on theinsulating layer 2 through sputtering Permalloy (NiFe). The seed layeris used for forming a bottom shield layer through plating.

Next, as shown in FIG. 2A and FIG. 2B, a magnetic material such asPermalloy (NiFe) of about 2 to 3 μm in thickness is selectivelydeposited on the seed layer by plating with a photoresist film as a maskto form a bottom shield layer 3 for a reproducing head. The bottomshield layer 3 corresponds to a first shield layer of the invention.Through the use of a photoresist film, the bottom shield layer 3 isformed to have a pair of grooves 3 a in which at least part of a pair ofconductive layers connected to the MR element is placed. Next, aninsulating film 4 of alumina, for example, whose thickness is 500 nm orabove is formed through sputtering, for example, on the bottom shieldlayer 3 including inside the grooves 3 a.

Next, as shown in FIG. 3A and FIG. 3B, a pair of conductive layers 5made of copper (Cu), for example, are formed inside the pair of grooves3 a of the bottom shield layer 3. The conductive layers 5 are to beleads connected to the MR element. The conductive layers 5 may be madeby selectively depositing copper inside the grooves 3 a to the thicknessof about 2 to 3 μm through plating with a photoresist film as a mask.Alternatively, the conductive layers 5 may be formed through sputtering.Next, an insulating layer 6 of alumina, for example, whose thickness is3 to 4 μm is formed all over the conductive layers 5 and the insulatingfilm 4.

Next, as shown in FIG. 4A and FIG. 4B, the insulating layer 6 ispolished to the surface of the bottom shield layer 3 and flattened. Thepolishing method may be mechanical polishing or chemical mechanicalpolishing (CMP). Through this flattening process, the surfaces of thebottom shield layer 3 and the conductive layer 5 are exposed. In thedrawings that follow FIG. 4A and FIG. 4B, the insulating film 4 and theinsulating layer 6 are shown as the one insulating layer 6.

As thus described, the conductive layers 5 are formed through plating tobe precisely embedded in the grooves 3 a of bottom shield layer 3 fullycovered with the insulating film 4 whose thickness is 500 nm or above.As a result, an extremely high insulation property is obtained betweenthe conductive layers 5 and the bottom shield layer 3. It is thereforepossible to prevent magnetic and electrical insulation faults betweenthe conductive layers 5 and the bottom shield layer 3 due to particlesor pinholes in the layers.

Next, as shown in FIG. 5A and FIG. 5B, an insulating material such asaluminum nitride or alumina is sputtered to a thickness of about 50 to100 nm over the bottom shield layer 3, the conductive layers 5 and theinsulating layer 6. A bottom shield gap film 7 a as an insulating layeris thus formed. Before forming the bottom shield gap film 7 a, aphotoresist pattern in a T-shape, for example, is formed to facilitateliftoff where contact holes are to be formed for electrically connectingthe conductive layers 5 to other conductive layers described later.After the bottom shield gap film 7 a is formed, the contact holes areformed through lifting off the photoresist patterns. Alternatively, thecontact holes may be formed by selectively etching the bottom shield gapfilm 7 a through the use of photolithography.

Next, an MR film of tens of nanometers in thickness for forming an MRelement 8 for reproduction is deposited through sputtering on the bottomshield gap film 7 a. A photoresist pattern (not shown) is thenselectively formed where the MR element 8 is to be formed on the MRfilm. The photoresist pattern is T-shaped, for example, to facilitateliftoff. Next, the MR film is etched through argon-base ion milling withthe photoresist pattern as a mask to form the MR element 8. The MRelement 8 may be either a GMR element or an AMR element.

Next, on the bottom shield gap film 7 a, a pair of conductive layers 9of 80 to 150 nm in thickness are formed through sputtering with the samephotoresist pattern as a mask. The conductive layers 9 are to beconnected to the MR element 8. The conductive layers 9 may be formedthrough stacking TiW, CoPt, TiW, Ta, and Au, for example. The conductivelayers 9 are electrically connected to the conductive layers 5 throughthe contact holes provided in the bottom shield gap film 7 a. Theconductive layers 9 and 5 make up the leads connected to the MR element8.

Next, on the bottom shield gap film 7 a, the MR element 8 and theconductive layers 9, an insulating material such as aluminum nitride oralumina is sputtered to a thickness of about 50 to 100 nm to form a topshield gap film 7 b as an insulating layer. The MR element 8 is thusembedded in the shield gap films 7 a and 7 b.

Next, a top shield layer-cum-bottom pole layer (called top shield layerin the following description) 10 made of a magnetic material is formedon the top shield gap film 7 b. The top shield layer 10 is used for bothreproducing and recording heads. The top shield layer 10 may be made ofNiFe or a high saturation flux density material such as FeN or acompound thereof or an amorphous of Fe—Co—Zr. The top shield layer 10may be made of layers of NiFe and a high saturation flux densitymaterial.

Next, an alumina film or a silicon dioxide film of 4 to 6 μm inthickness is formed over the entire surface. The entire surface is thenflattened so that the surface of the top shield layer 10 is exposed. Theflattening may be performed through mechanical polishing or CMP. Such aflattening process prevents formation of a rise in the top shield layer10 caused by the pattern of the MR element 8. The surface of the topshield layer 10 is thus made flat, and the recording gap layer of themagnetic pole of the recording head to be formed is made flat. As aresult, the writing property in a high frequency range is improved.

Next, as shown in FIG. 6A and FIG. 6B, an insulating film of alumina orsilicon dioxide of 1 to 2 μm in thickness is formed on the flattened topshield layer 10. The insulating film is then selectively etched throughphotolithography to form an insulating layer 11 that defines the throatheight. A taper is formed in the edge on the pole portion side of theinsulating layer 11. The tapered edge defines the throat height.

Next, a recording gap layer 12 made of an insulating film of alumina,for example, is formed on the top shield layer 10 and the insulatinglayer 11. A rearward portion of the recording gap layer 12 (the rightside of FIG. 6A) is then selectively etched to form a magnetic path.Next, a top pole tip 13 and a magnetic layer 14 whose thickness is about3 μm are formed on the recording gap layer 12. The top pole tip 13determines the track width of the induction recording head. The magneticlayer 14 makes up a magnetic path. The top pole tip 13 and the magneticlayer 14 may be formed through plating with NiFe (50 weight % Ni and 50weight % Fe), or through sputtering a high saturation flux densitymaterial such as FeN or a compound thereof and then patterning. Besidesthe above examples, the material of the top pole tip 12 may be NiFe (80weight % Ni and 20 weight % Fe) or a high saturation flux densitymaterial such as an amorphous of Fe—Co—Zr. Alternatively, the top polelayer 13 may be layers of two or more of the above materials. The toppole layer 13 made of a high saturation flux density material allows themagnetic flux generated by the coil described later to effectively reachthe pole portion without saturating before reaching the pole. Arecording head that achieves high recording density is thereforeobtained.

Next, part of the recording gap layer 12 on both sides of the top poletip 13 is removed through dry etching. The exposed top shield layer 10is then etched through ion milling by about 0.4 μm with the top pole tip13 as a mask so as to form a trim structure.

Next, as shown in FIG. 7A and FIG. 7B, on the recording gap layer 12 inthe region where the insulating layer 11 is formed, a thin-film coil 15of a first layer for the recording head is formed through plating, forexample, whose thickness is 2 to 3 μm.

Next, as shown in FIG. 8A and FIG. 8B, an insulating layer 16 made ofphotoresist is formed into a specific pattern on the insulating layer 11and the coil 15. Next, a thin-film coil 17 of a second layer whosethickness is 2 to 3 μm is formed on the insulating layer 16. Aninsulating layer 18 made of photoresist is formed into a specificpattern on the insulating layer 16 and the coil 17. Next, the entirestructure is cured at a temperature in the range between 200 to 250° C.,such as about 200° C.

Next, as shown in FIG. 9A and FIG. 9B, a top yoke layer 19 of about 3 to4 μm in thickness is formed through plating to cover the magnetic layer14, the insulating layers 16 and 18, and a rearward portion of the toppole tip 13.

The upper one of the magnetic layers of the recording head is thusdivided into the top pole tip 13 and the top yoke layer 19. As a result,the microstructured top pole tip 13 is obtained and the recording headwith the submicron track width is easily achieved. The top yoke layer 19is brought to contact with the top pole tip 13 on the total of foursurfaces including the top surface and the three lateral surfaces of thetop pole tip 13. As a result, the magnetic flux passing through the topyoke layer 19 efficiently flows into the top pole tip 13 withoutsaturating. The recording head that achieves high recording density istherefore obtained. The top pole layer is made up of the top pole tip13, the top yoke layer 19 and the magnetic layer 14 in combination.

The trim structure is obtained by etching the top shield layer 10 withthe microstructured top pole tip 13 as a mask. The trim structuresuppresses an increase in the effective track width due to expansion ofthe magnetic flux generated during writing in a narrow track.

Next, as shown in FIG. 10A and FIG. 10B, an overcoat layer 20 ofalumina, for example, is formed to cover the top yoke layer 19. Finally,machine processing of the slider is performed and the air bearingsurface of the recording head and the reproducing head is formed. Thethin-film magnetic head is thus completed.

The top shield layer (bottom pole layer) 10, the top pole tip 13, themagnetic layer 14, and the thin-film coils 15 and 17 correspond to aninduction-type magnetic transducer of the invention. That is, the topshield layer (bottom pole layer) 10 corresponds to one of the twomagnetic layers of the recording head of the invention. The top pole tip13, the magnetic layer 14 and the top yoke layer 19 correspond to theother of the two magnetic layers. The top shield layer 10 corresponds toa second shield layer of the invention as well.

FIG. 11 is a top view of the bottom shield layer 3. FIG. 12 is a topview of the thin-film magnetic head of the embodiment manufacturedthrough the foregoing process. The overcoat layer 20 is omitted in FIG.12. FIG. 12 shows the state before mechanical processing of the slideris performed. FIG. 1A to FIG. 10A are cross sections taken along line10A—10A of FIG. 12. FIG. 1B to FIG. 10B are cross sections taken alongline 10B—10B of FIG. 12. As shown in the drawings, the bottom shieldlayer 3 extends from the region facing the MR element 8 and itsperiphery to both sides of the MR element 8. Part of the bottom shieldlayer 3 passes through the region facing the top shield layer 10. Mostof the remaining part is placed around the region facing the twomagnetic layers of the induction-type magnetic transducer (the topshield layer 10, the top pole tip 13, the magnetic layer 14 and the topyoke layer 19) and the thin-film coils 15 and 17. The grooves 3 a of thebottom shield layer 3 extend from the positions near both ends of the MRelement 8 to both sides of the MR element 8. Part of the grooves 3 apasses through the region facing the top shield layer 10. Most of theremaining part is placed around the region facing the two magneticlayers of the induction-type magnetic transducer and the thin-film coils15 and 17. The conductive layers 5 making up the lead connected to theMR element 8 are embedded in the grooves 3 a of the bottom shield layer3, being insulated. Therefore, the conductive layers 5 extend from thepositions near both ends of the MR element 8 to both sides of the MRelement 8. Part of the conductive layers 5 pass through the regionfacing the top shield layer 10. Most of the remaining part is placedaround the region facing the two magnetic layers of the induction-typemagnetic transducer and the thin-film coils 15 and 17. The ends of theconductive layers 5 opposite to the MR element 8 are greater in widththan the grooves 3 a and placed outside the bottom shield layer 3.

The shape of the bottom shield layer 3 is not limited to the one shownin FIG. 11. For example, as shown in FIG. 13, part of the bottom shieldlayer 3 inside the grooves 3 a may be formed in the entire region facingthe two magnetic layers of the magnetic transducer and the thin-filmcoils 15 and 17. Alternatively, as shown in FIG. 14, a single groove 3 bmay be formed in the bottom shield layer 3 shown in FIG. 13 in place ofthe pair of grooves 3 a. The groove 3 b takes the shape of the pair ofgrooves 3 a coupled to each other. The groove 3 b divides the bottomshield layer 3 into a portion 3A outside the groove 3 b and a portion 3Binside the groove 3 b.

In the embodiment, the bottom shield layer 3 has the grooves 3 a. Themost part of the conductive layers 5 making up the leads connected tothe MR element 8 is placed in the grooves 3 a, being insulated from thebottom shield layer 3 by the insulating film 4. As a result, accordingto the embodiment of the invention, an extremely high insulationproperty is achieved between the conductive layers 5 and the bottomshield layer 3. It is therefore possible to prevent magnetic andelectrical insulation faults between the conductive layers 5 and thebottom shield layer 3.

Part of the conductive layers 5 faces the top shield layer 10 with thebottom shield gap film 7 a and the top shield gap film 7 b in between.However, the most part of the conductive layers 5 does not face the topshield layer 10. As a result, the insulation property is extremely highbetween the conductive layers 5 and the top shield layer 10. It istherefore possible to prevent magnetic and electrical insulation faultsbetween the conductive layers 5 and the bottom shield layer 10.

According to the invention, the conductive layers 5 are not insertedbetween the bottom shield gap film 7 a and the top shield gap film 7 b.As a result, it is impossible that large areas of the conductive layers5 face the bottom shield layer 3 and the top shield layer 10 with thebottom shield gap film 7 a and the top shield gap film 7 b in between.Therefore, although the bottom shield gap film 7 a and the top shieldgap film 7 b are made thin, the insulation property is maintained at ahigh level between the conductive layers 5 and the bottom shield layer 3and between the conductive layers 5 and the top shield layer 10.

According to the embodiment described so far, the insulation property isimproved between the conductive layers connected to the MR element 8 andthe bottom shield layer 3 and between the conductive layers and the topshield layer 10 without increasing the thickness of the bottom shieldgap film 7 a and the top shield gap film 7 b.

According to the embodiment, the bottom shield gap film 7 a and the topshield gap film 7 b are made thin enough to improve the thermalasperity. The property of the reproducing head is thereby improved.

According to the embodiment, the conductive layer 5 is made thick enoughso that the wiring resistance of the conductive layer connected to theMR element 8 is low. As a result, it is possible to detect withsensitivity a minute change in the output signal corresponding to aminute change in resistance of the MR element 8. The property of thereproducing head is improved in this respect, too.

In the embodiment, lateral surfaces of part of the conductive layers 5placed in the grooves 3 a of the bottom shield layer 3 are shielded,being placed in the middle of the bottom shield layer 3 along thedirection of length. As a result, it is possible to reduce the effectsof noises caused by internal factors such as magnetism and the likegenerated by the coil of the induction-type recording head or externalfactors such as the motor of the hard disk drive. In the neighborhood ofthe MR element 8, in particular, both sides of the conductive layers 5are shielded by the bottom shield layer 3 and the top surfaces of theconductive layers 5 are shielded by the top shield layer 10. The effectsof noises on the conductive layers 5 are thereby reduced. The propertyof the reproducing head is improved in this respect, too.

According to the embodiment, the thick insulating layer 11 is formedbetween the coils 15 and 17 and the top shield layer 10, in addition tothe thin recording gap layer 12. As a result, a high insulation strengthis achieved between the coils 15 and 17 and the top shield layer 10.Magnetic flux leakage from the coils 15 and 17 is reduced as well.

[Second Embodiment]

Reference is now made to FIG. 15 to describe a second embodiment of theinvention. FIG. 15 is a top view of a thin-film magnetic head of theembodiment. The overcoat layer 20 is omitted in FIG. 15. FIG. 15 showsthe state before mechanical processing of the slider is performed.

The thin-film magnetic head of the embodiment includes shield layers 21for the conductive layers. The shield layers 21 face the portions of theconductive layers 5 in the grooves 3 a of the bottom shield layer 3 thatare exposed from the grooves 3. The shield layers 21 cover at leastportions of the conductive layers 5 in the grooves 3 a that do not facethe top shield layer 10. Where the insulating layer 11 is provided, theshield layers 21 are formed on the insulating layer 11. The shieldlayers 21 are formed on the top shield gap film 7 b where the insulatinglayer 11 is not provided.

In the step of making the top yoke layer 19, the shield layers 21 may beformed at the same time through the use of the same magnetic material.

According to the embodiment, the shield layers 21 shield the topsurfaces of the portions of the conductive layers 5 in the grooves 3 athat do not face the top shield layer 10. As a result, the effects ofnoises on the conductive layers 5 are more greatly reduced, compared tothe first embodiment.

The remainder of configuration, functions and effects of the embodimentare similar to those of the first embodiment.

[Third Embodiment]

Reference is now made to FIG. 16A and FIG. 16B to describe a thirdembodiment of the invention. FIG. 16A is a cross section of a thin-filmmagnetic head of the embodiment orthogonal to the air bearing surface.FIG. 16B is a cross section of the pole portion of the thin-filmmagnetic head of the embodiment parallel to the air bearing surface.FIG. 16A shows the state before mechanical processing of the slider isperformed.

The thin-film magnetic head of the embodiment comprises a seed layer 31used for forming the bottom shield layer 3 and electrically connected tothe bottom shield layer 3. The seed layer 31 is formed in a regionlarger than the region where the bottom shield layer 3 is formed. Theseed layer 31 is formed in the almost entire region between the pair ofconductive layers 5, for example.

The seed layer 31 is made of Permalloy (NiFe) through sputtering, forexample, on the insulation layer 2 and has a thickness of 50 to 100 nm.The bottom shield layer 3 is selectively formed through plating on theseed layer 31 with a photoresist film as a mask.

According to the embodiment, the seed layer 31 is connected to thebottom shield layer 3. The seed layer 3 is formed in the region largerthan the region where the bottom shield layer 3 is formed. The seedlayer 31 thus functions as a shield together with the bottom shieldlayer 3. As a result, the shield region provided for the MR element 8 islarger than that of the first embodiment. The influence of noises froman external source is thereby more greatly reduced.

As in the second embodiment, the shield layers 21 facing the part of theconductive layers 5 in the grooves 3 a of the bottom shield layer 3 thatis exposed from the grooves 3 a may be provided as well in thisembodiment.

The remainder of configuration, functions and effects of the embodimentare similar to those of the first embodiment.

[Fourth Embodiment]

Reference is now made to FIG. 17A and FIG. 17B to describe a fourthembodiment of the invention. FIG. 17A is a cross section of a thin-filmmagnetic head of the embodiment orthogonal to the air bearing surface.FIG. 17B is a cross section of the pole portion of the thin-filmmagnetic head of the embodiment parallel to the air bearing surface.FIG. 17A shows the state before mechanical processing of the slider isperformed.

In the thin-film magnetic head of the embodiment, the area in which thebottom shield layer 3 is formed is greater than that of the firstembodiment. The bottom shield layer 3 of the fourth embodiment may beformed in the almost entire region between the pair of conductive layers5, for example, in addition to the region where the bottom shield layer3 of the first embodiment is formed. The bottom shield layer 3 isselectively formed on the seed layer 31 through plating with aphotoresist film as a mask. In the embodiment the seed layer 31 isformed in the almost entire region between the pair of conductive layers5 as in the third embodiment.

According to the embodiment, the area in which the bottom shield layer 3is formed is greater than that of the first embodiment. The shieldregion for the MR element 8 is thereby made greater and the influence ofnoises from an external source is more greatly reduced.

The remainder of configuration, functions and effects of the embodimentare similar to those of the first embodiment.

[Fifth Embodiment]

Reference is now made to FIG. 18 to FIG. 20 to describe a fifthembodiment of the invention. FIG. 18 is a top view of a thin-filmmagnetic head of the embodiment. The overcoat layer is omitted in FIG.18. FIG. 18 shows the state before mechanical processing of the slideris performed. FIG. 19 is a top view of a bottom shield layer of theembodiment. FIG. 20 is a top view of conductive layers of theembodiment.

In the embodiment a bottom shield layer 53 is provided in place of thebottom shield layer 3 of the first embodiment. The bottom shield layer53 extends from the region facing the MR element 8 and its periphery tothe region facing the neighborhood of the center of the coils 15 and 17.In the embodiment a pair of conductive layers 55 are provided in placeof the conductive layers 5 of the first embodiment. In the bottom shieldlayer 53 a pair of grooves 53 a are formed in which portions of theconductive layers 5 are placed. The grooves 53 a extend from theneighborhood of ends of the MR element 8 to sides of the MR element 8.The grooves 53 a then extend along the neighborhood of the periphery ofthe bottom shield layer 53 and reach the end of the bottom shield layer53 opposite to the pole portion. Therefore, in the embodiment thegrooves 53 a of the bottom shield layer 53 pass through the regionfacing the two magnetic layers and the thin-film coils 15 and 17 of theinduction-type magnetic transducer.

Portions of the conductive layers 55 closer to the MR element 8 areplaced in the grooves 53 a of the bottom shield layer 53, beinginsulated. The remaining portions of the conductive layers 55 are placedoutside the bottom shield layer 53 and extend from the end of the bottomshield layer 53 opposite to the pole portion to the region further awayfrom the pole portion. The end of each of the conductive layers 55 isgreater than each of the grooves 53 a in width.

The remainder of configuration, functions and effects of the embodimentare similar to those of the first embodiment.

[Sixth Embodiment]

Reference is now made to FIG. 21 and FIG. 22 to describe a sixthembodiment of the invention. FIG. 21 is a top view of a bottom shieldlayer and conductive layers of the embodiment. FIG. 22 is a top view ofthe main part of a thin-film magnetic head of the embodiment.

In the embodiment a bottom shield layer 63 is provided in place of thebottom shield layer 3 of the first embodiment. The bottom shield layer63 is divided into a portion 63A facing the MR element 8 and portions63B and 63C not facing the MR element 8. Specific gaps are provided eachbetween the portion 63A and the portion 63B and between the portion 63Aand the portion 63C. As the grooves 3 a of the bottom shield layer 3 ofthe first embodiment, grooves 63 a are formed in the bottom shield layer63. Portions of the conductive layers 5 are placed in the grooves 63 a.The portions 63B and 63C are each divided into two parts by the grooves63 a. Therefore the bottom shield layer 63 is actually divided into thefive portions. Such a bottom shield layer 63 may be selectively formedthrough plating with a photoresist film as a mask on part of the seedlayer selectively left through etching that corresponds to the bottomshield layer 63.

As in the second embodiment, the shield layers 21 are provided in thisembodiment. The shield layers 21 face the portions of the conductivelayers 5 in the grooves 63 a of the bottom shield layer 63 that areexposed from the grooves 63 a.

According to the embodiment, the bottom shield layer 63 is divided intothe five portions. Therefore, the area of each portion is small and theshield property in a high frequency range is improved.

The remainder of configuration, functions and effects of the embodimentare similar to those of the second embodiment.

In the first to sixth embodiments one of the two shield layers facingeach other with the MR element in between has the grooves in which atleast part of the conductive layers connected to the MR element isplaced. At least part of the conductive layers is placed in the grooves,being insulated form the shield layer. As a result, according to theembodiments, the insulation property is improved between the conductivelayers and each shield layer. Furthermore, since the conductive layersare not placed between the shield layers with insulating layers inbetween, the insulation property is improved between each shield layerand the conductive layers connected to the MR element without increasingthe thickness of the insulating layer between the MR element and eachshield layer. According to the embodiments, it is possible to fabricatethe conductive layers sufficiently thick. The wiring resistance of theconductive layers is thereby reduced. According to the embodiments, partof the conductive layers placed in the grooves is shielded, being heldin the middle of one of the shield layers. The effects of noises on theconductive layers are thereby reduced.

If the shield layers for shielding at least part of the conductivelayers are provided, the effects of noises on the conductive layers arefurther reduced.

The seed layer may be provided that is used for fabricating the one ofthe shield layers and formed in the region larger than the region wherethe one of the shield layers is formed. The seed layer is electricallyconnected to the one of the shield layers. The shield region for the MRelement is thereby increased and the effects of noises from an externalsource are further reduced.

The one of the shield layers may be divided into the portion facing theMR element and the portions not facing the MR element. The shieldproperty in a high frequency range is thereby improved.

[Seventh Embodiment]

Reference is now made to FIG. 23A to FIG. 31A, FIG. 23B to FIG. 31B,FIG. 32 and FIG. 33 to describe a composite thin-film magnetic head anda method of manufacturing the same of a seventh embodiment of theinvention. FIG. 23A to FIG. 31A are cross sections each orthogonal tothe air bearing surface of the thin-film magnetic head. FIG. 23B to FIG.31B are cross sections each parallel to the air bearing surface of thepole portion of the head.

In the method of the embodiment, as shown in FIG. 23A and FIG. 23B, aninsulating layer 102 made of alumina (Al₂O₃), for example, of about 5 to10 μm in thickness is deposited on a substrate 101 made of aluminumoxide and titanium carbide (Al₂O₃-TiC), for example.

Although not shown, a seed layer is made on the insulating layer 102through sputtering Permalloy (NiFe). The seed layer is used for forminga bottom shield layer and a pair of conductive layers to be leadsconnected to an MR element through plating.

Next, as shown in FIG. 24A and FIG. 24B, part of the seed layer isselectively etched through ion milling, for example, with a photoresistfilm as a mask. The part of the seed layer thereby removed is the regionexcept the regions where the bottom shield layer and the conductivelayers are to be formed. The region where the bottom shield layer is tobe formed includes grooves in which the conductive layers are to beplaced. The regions where the conductive layers are to be formed arelocated in the groove s. The regions where the conductive layers are tobe formed are each 1 to 3 μm in width, for example. The space is 1 μm,for example, between the regions where the conductive layers are to beformed and the region where the bottom shield layer is to be formed.

Next, a magnetic material such as Permalloy (NiFe) of about 2 to 3 μm inthickness is selectively deposited on the seed layer by plating with aphotoresist film as a mask to form the conductive layers 104 and thebottom shield layer 103 for a reproducing head. In such a manner thebottom shield layer 103 and the conductive layers 104 are made of thesame material at the same time. The bottom shield layer 103 correspondsto the first shield layer of the invention. The bottom shield layer 103thus formed has the grooves 103 a in which the conductive layers 104 areplaced. The conductive layer 104 is placed in the groove 103 a with aspecific space from the other conductive layer 104. The conductivelayers 104 are each 1 to 3 μm in width, for example. The space is 1 μm,for example, between the conductive layer 104 and the bottom shieldlayer 103. The conductive layers 104 are electrically insulated from thebottom shield layer 103 since the seed layer between the conductivelayers 104 and the bottom shield layer 103 has been removed.

Alternatively, the bottom shield layer 103 and the conductive layers 104may be fabricated through forming layers by sputtering and selectivelyetching the layers by dry etching.

Next, an insulating film 105 of alumina, for example, whose thickness is3 to 4 μm is formed in the gap between the bottom shield layer 103 andthe conductive layers 104 and over the entire surface of the bottomshield layer 103 and the conductive layers 104.

Next, as shown in FIG. 25A and FIG. 25B, the insulating film 105 ispolished to the surfaces of the bottom shield layer 103 and theconductive layers 104 and flattened. The polishing method may bemechanical polishing or CMP. Through this flattening process, thesurfaces of the bottom shield layer 103 and the conductive layers 104are exposed.

As thus described, the conductive layers 104 are formed in the grooves103 a of the bottom shield layer 103, being insulated from the bottomshield layer 103 by the insulating layer 105 of 1 μm in thickness, forexample. As a result, an extremely high insulation property is obtainedbetween the conductive layers 104 and the bottom shield layer 103. It istherefore possible to prevent magnetic and electrical insulation faultsbetween the conductive layers 104 and the bottom shield layer 103 due toparticles or pinholes in the layers.

Next, as shown in FIG. 26A and FIG. 26B, an insulating material such asaluminum nitride or alumina is sputtered to a thickness of about 50 to100 nm over the bottom shield layer 103, the conductive layers 104 andthe insulating film 105. A bottom shield gap film 107 a as an insulatinglayer is thus formed. Before forming the bottom shield gap film 107 a, aphotoresist pattern in a T-shape, for example, is formed to facilitateliftoff where contact holes are to be formed for electrically connectingthe conductive layers 104 to other conductive layers described later.After the bottom shield gap film 107 a is formed, the contact holes areformed through lifting off the photoresist patterns. The contact holesmay be formed by selectively etching the bottom shield gap film 107 athrough the use of photolithography.

Next, an MR film of tens of nanometers in thickness for forming an MRelement 108 for reproduction is deposited through sputtering on thebottom shield gap film 107 a. A photoresist pattern (not shown) is thenselectively formed where the MR element 108 is to be formed on the MRfilm. The photoresist pattern may be T-shaped, for example, tofacilitate liftoff. Next, the MR film is etched through argon-base ionmilling with the photoresist pattern as a mask to form the MR element108. The MR element 108 may be either a GMR element or an AMR element.

Next, on the bottom shield gap film 107 a, a pair of conductive layers109 of 80 to 150 nm in thickness are formed through sputtering with thesame photoresist pattern as a mask. The conductive layers 109 are to beelectrically connected to the MR element 108. The conductive layers 109may be formed through stacking TiW, CoPt, TiW, Ta, and Au, for example.The conductive layers 109 are electrically connected to the conductivelayers 104 through the contact holes provided in the bottom shield gapfilm 107 a. The conductive layers 109 and 104 make up the leadsconnected to the MR element 108.

Next, on the bottom shield gap film 107 a, the MR element 108 and theconductive layers 109, an insulating material such as aluminum nitrideor alumina is sputtered to a thickness of about 50 to 100 nm to form atop shield gap film 107 b as an insulating layer. The MR element 108 isthus embedded in the shield gap films 107 a and 107 b.

Next, a top shield layer-cum-bottom pole layer (called top shield layerin the following description) 110 made of a magnetic material is formedon the top shield gap film 107 b. The top shield layer 110 is used forboth reproducing and recording heads. The top shield layer 110 may bemade of NiFe or a high saturation flux density material such as FeN or acompound thereof or an amorphous of Fe—Co—Zr. The top shield layer 110may be made of layers of NiFe and a high saturation flux densitymaterial.

Next, an alumina film or a silicon dioxide film of 4 to 6 μm inthickness is formed over the entire surface. The entire surface is thenflattened so that the surface of the top shield layer 110 is exposed.The flattening may be performed through mechanical polishing or CMP.Such a flattening process prevents formation of a rise in the top shieldlayer 110 caused by the pattern of the MR element 108. The surface ofthe top shield layer 110 is thus made flat, and a recording gap layer ofthe magnetic pole of the recording head to be formed is made flat. As aresult, the writing property in a high frequency range is improved.

Next, as shown in FIG. 27A and FIG. 27B, an insulating film of aluminaor silicon dioxide of 1 to 2 μm in thickness is formed on the flattenedtop shield layer 110. The insulating film is then selectively etchedthrough photolithography to form an insulating layer 111 that definesthe throat height. A taper is formed in the edge on the pole portionside of the insulating layer 111. The tapered edge defines the throatheight.

Next, a recording gap layer 112 made of an insulating film of alumina,for example, is formed on the top shield layer 110 and the insulatinglayer 111. The rearward (the right side of FIG. 27A) portion of therecording gap layer 112 is then selectively etched to form a magneticpath. Next, a top pole tip 113 and a magnetic layer 114 whose thicknessis about 3 μm are formed on the recording gap layer 112. The top poletip 113 determines the track width of the induction recording head. Themagnetic layer 114 makes up a magnetic path. The top pole tip 113 andthe magnetic layer 114 may be formed through plating with NiFe (50weight % Ni and 50 weight % Fe), or through sputtering a high saturationflux density material such as FeN or a compound thereof and thenpatterning. Besides the above examples, the material of the top pole tip112 may be NiFe (80 weight % Ni and 20 weight % Fe) or a high saturationflux density material such as an amorphous of Fe—Co—Zr. Alternatively,the top pole tip 113 may be layers of two or more of the abovematerials. The top pole tip 113 made of a high saturation flux densitymaterial allows the magnetic flux generated by the coil described laterto effectively reach the pole portion without saturating before reachingthe pole. The recording head that achieves high recording density istherefore obtained.

Next, part of the recording gap layer 112 on both sides of the top poletip 113 is removed through dry etching. The exposed top shield layer 110is then etched through ion milling by about 0.4 μm, for example, withthe top pole tip 113 as a mask so as to form a trim structure.

Next, as shown in FIG. 28A and FIG. 28B, on the recording gap layer 112in the region where the insulating layer 111 is formed, a thin film coil115 of a first layer for the recording head is formed through plating,for example, whose thickness is 2 to 3 μm.

Next, as shown in FIG. 29A and FIG. 29B, an insulating layer 116 made ofphotoresist is formed into a specific pattern on the insulating layer111 and the coil 115. Next, a thin film coil 117 of a second layer whosethickness is 2 to 3 μm is formed on the insulating layer 116. Aninsulating layer 118 made of photoresist is then formed into a specificpattern on the insulating layer 118 and the coil 117. Next, the entirestructure is cured at a temperature in the range between 200 to 250° C.,such as about 200°.

Next, as shown in FIG. 30A and FIG. 30B, a top yoke layer 119 of about 3to 4 μm in thickness is formed through plating to cover the magneticlayer 114, the insulating layers 116 and 118, and a rearward portion ofthe top pole tip 113.

The upper one of the magnetic layers of the recording head is thusdivided into the top pole tip 113 and the top yoke layer 119. As aresult, the microstructured top pole tip 113 is obtained and therecording head with the submicron track width is easily achieved. Thetop yoke layer 119 is brought to contact with the top pole tip 113 onthe total of four surfaces including the top surface and the threelateral surfaces of the top pole tip 113. As a result, the magnetic fluxpassing through the top yoke layer 119 efficiently flows into the toppole tip 113 without saturation. The recording head that achieves highrecording density is therefore obtained. The top pole layer is made upof the top pole tip 113, the top yoke layer 119 and the magnetic layer114 in combination.

The trim structure is obtained by etching the top shield layer 110 withthe microstructured top pole tip 113 as a mask. The trim structuresuppresses an increase in the effective track width due to expansion ofthe magnetic flux generated during writing in the narrow track.

Next, as shown in FIG. 31A and FIG. 31B, an overcoat layer 120 ofalumina, for example, is formed to cover the top yoke layer 119.Finally, machine processing of the slider is performed and the airbearing surface of the recording head and the reproducing head isformed. The thin-film magnetic head is thus completed.

The top shield layer (bottom pole layer) 110, the top pole tip 113, themagnetic layer 114, the top yoke layer 119 and the thin-film coils 115and 117 correspond to the induction-type magnetic transducer of theinvention. That is, the top shield layer (bottom pole layer) 110corresponds to one of the two magnetic layers of the recording head ofthe invention. The top pole tip 113, the magnetic layers 114 and the topyoke layer 119 correspond to the other of the two magnetic layers. Thetop shield layer 110 corresponds to the second shield layer of theinvention as well.

FIG. 32 is a top view of the bottom shield layer 103 and the conductivelayers 104. FIG. 33 is a top view of the thin-film magnetic head of theembodiment manufactured through the foregoing process. In FIG. 33 theovercoat layer 120 is omitted. FIG. 33 shows the state before mechanicalprocessing of the slider is performed. FIG. 23A to FIG. 31A are crosssections taken along line 31A-31A of FIG. 33. FIG. 23B to FIG. 31B arecross sections taken along line 31B-31B of FIG. 33. As shown in thedrawings, the bottom shield layer 103 is placed in the region includingthe region facing the MR element 108 and its periphery and the regionfacing the two magnetic layers of the induction-type magnetic transducer(the top shield layer 110; and the top pole tip 113, the magnetic layer114 and the top yoke layer 119) and the thin-film coils 115 and 117. Thegrooves 103 a of the bottom shield layer 103 extend from the positionsnear both ends of the MR element 108 to both sides of the MR element108. Portions of the grooves 103 a pass through the region facing thetop shield layer 110. Most of the remaining portions is placed aroundthe region facing the two magnetic layers of the induction-type magnetictransducer and the thin-film coils 115 and 117. The conductive layers104 making up the leads connected to the MR element 108 are placed inthe grooves 103 a of the bottom shield layer 103, being insulated. Theends of the conductive layers 104 opposite to the MR element 108 aregreater in width than the grooves 103 a and placed outside the bottomshield layer 103.

In the embodiment, the bottom shield layer 103 has the grooves 103 a.The most part of the conductive layers 104 making up the lead connectedto the MR element 108 is placed in the grooves 103 a, being insulatedfrom the bottom shield layer 103 by the insulating film 10O. As aresult, according to the embodiment of the invention, an extremely highinsulation property is achieved between the conductive layers 104 andthe bottom shield layer 103. It is therefore possible to preventmagnetic and electrical insulation faults between the conductive layers104 and the bottom shield layer 103.

Part of the conductive layers 104 faces the top shield layer 110 withthe bottom shield gap film 107 a and the top shield gap film 107 b inbetween. However, the most part of the conductive layers 104 does notface the top shield layer 110. As a result, the insulation property isextremely high between the conductive layers 104 and the top shieldlayer 110. It is therefore possible to prevent magnetic and electricalinsulation faults between the conductive layers 104 and the bottomshield layer 110.

According to the invention, the conductive layers 104 are not insertedbetween the bottom shield gap film 107 a and the top shield gap film 107b. As a result, it is impossible that large areas of the conductivelayers 104 face the bottom shield layer 103 and the top shield layer 110with the bottom shield gap film 107 a and the top shield gap film 107 bin between. Therefore, although the bottom shield gap film 107 a and thetop shield gap film 107 b are thin, the insulation property ismaintained at a high level between the conductive layers 104 and thebottom shield layer 103 and between the conductive layers 104 and thetop shield layer 110.

According to the embodiment described so far, the insulation property isimproved between the conductive layers connected to the MR element 108and the bottom shield layer 103 and between the conductive layers andthe top shield layer 110 without increasing the thickness of the bottomshield gap film 107 a and the top shield gap film 107 b.

According to the embodiment, the bottom shield gap film 107 a and thetop shield gap film 107 b are made thin enough to improve the thermalasperity. The property of the reproducing head is thereby improved.

According to the embodiment, the conductive layers 104 are made thickenough so that the wiring resistance of the conductive layers connectedto the MR element 108 is reduced. As a result, it is possible to detectwith sensitivity a minute change in the output signal corresponding to aminute change in resistance of the MR element 108. The property of thereproducing head is improved in this respect, too.

In the embodiment, the sides of part of the conductive layers 104 placedin the grooves 103 a of the bottom shield layer 103 are shielded, beingplaced in the middle of the bottom shield layer 103 along the directionof length. As a result, it is possible to reduce the effects of noisescaused by internal factors such as magnetism and the like generated bythe coil of the induction-type recording head or external factors suchas the motor of the hard disk drive. In the neighborhood of the MRelement 108, in particular, both sides of the conductive layers 104 areshielded by the bottom shield layer 103 and the top surface of theconductive layers 104 is shielded by the top shield layer 110. Theeffects of noises on the conductive layers 104 are thereby reduced. Theproperty of the reproducing head is improved in this respect, too.

According to the embodiment, the bottom shield layer 103 and theconductive layers 104 are made of the same material at the same time. Asa result, the number of manufacturing steps is reduced, compared to thecase in which the bottom shield layer 103 and the conductive layers 104are made in different steps.

According to the embodiment, the thick insulating layer 111 is formedbetween the coils 115 and 117 and the top shield layer 110, in additionto the thin recording gap layer 112. As a result, a high insulationstrength is achieved between the coils 115 and 117 and the top shieldlayer 110. Magnetic flux leakage from the coils 115 and 117 is reducedas well.

[Eighth Embodiment]

Reference is now made to FIG. 34 to describe an eighth embodiment of theinvention. FIG. 34 is a top view of a thin-film magnetic head of theembodiment. The overcoat layer is omitted in FIG. 34. FIG. 34 shows thestate before mechanical processing of the slider is performed.

The thin-film magnetic head of the embodiment includes shield layers 121for the conductive layers. The shield layers 121 face the portions ofthe conductive layers 104 in the grooves 103 a of the bottom shieldlayer 103 that are exposed from the grooves 103. The shield layers 121cover at least portions of the conductive layers 104 in the grooves 3 athat do not face the top shield layer 110. Where the insulating layer111 is provided, the shield layers 121 are formed on the insulatinglayer 111. The shield layers 121 are formed on the top shield gap film107 b where the insulating layer 111 is not provided.

In the step of making the top yoke layer 119, the shield layers 121 maybe formed at the same time through the use of the same magneticmaterial.

According to the embodiment, the shield layers 121 shield the topsurfaces of the portions of the conductive layers 104 in the grooves 103a that do not face the top shield layer 110. As a result, the effects ofnoises on the conductive layers 104 are more greatly reduced, comparedto the seventh embodiment.

The remainder of configuration, functions and effects of the embodimentare similar to those of the seventh embodiment.

[Ninth Embodiment]

Reference is now made to FIG. 35A, FIG. 35B and FIG. 36 to describe aninth embodiment of the invention. FIG. 35A is a cross section of athin-film magnetic head of the embodiment orthogonal to the air bearingsurface. FIG. 35B is a cross section of the pole portion of thethin-film magnetic head parallel to the air bearing surface. FIG. 36 isa top view of the thin-film magnetic head. FIG. 35A and FIG. 36 show thestate before mechanical processing of the slider is performed.

In the thin-film magnetic head of the embodiment, as shown in FIG. 36,the bottom shield layer 103 has a configuration similar to that of thebottom shield layer 103 of the seventh embodiment except that theportion between the pair of conductive layers 104 is removed. Therefore,in the ninth embodiment, as shown in FIG. 35A, the outer lateralsurfaces of the conductive layers 104 face the bottom shield layer 103.The inner lateral surfaces of the conductive layers 104 do not face thebottom shield layer 103 but face the insulating film 105. As in theeighth embodiment, the shield layers 121 facing the conductive layers104 are provided

In the ninth embodiment, although the inner lateral surfaces of theconductive layers 104 do not face the bottom shield layer 103, the outerlateral surfaces of the conductive layers 104 are shielded by the bottomshield layer 103. The shield layers 121 shield the top surfaces of theportions of the conductive layers 104 not facing the top shield layer110. As a result, the effects of noises on the conductive layers 104 aresufficiently reduced.

The remainder of configuration, functions and effects of the embodimentare similar to those of the eighth embodiment.

[Tenth Embodiment]

Reference is now made to FIG. 37A, FIG. 37B and FIG. 38 to describe atenth embodiment of the invention. FIG. 37A is a cross section of athin-film magnetic head of the embodiment orthogonal to the air bearingsurface. FIG. 37B is a cross section of the pole portion of thethin-film magnetic head parallel to the air bearing surface. FIG. 38 isa top view of the thin-film magnetic head. FIG. 37A and FIG. 38 show thestate before mechanical processing of the slider is performed.

As in the ninth embodiment, the bottom shield layer 103 has aconfiguration similar to that of the bottom shield layer 103 of theseventh embodiment except that the portion between the pair ofconductive layers 104 is removed.

The thin-film magnetic head of the embodiment comprises seed layers 131used for forming the conductive layers 104 and electrically connected tothe conductive layers 104. The seed layers 131 are formed in a regionlarger than the region where the conductive layers 104 are formed. Theseed layers 131 may be formed in a large region between the pair ofconductive layers 104, for ex ample. As shown in FIG. 38, one of theseed layers 131 electrically connected to one of the conductive layers104 is separated and insulated from the other seed layer 131 connectedto the other conductive layer 104.

The seed layers 131 are made of Permalloy (NiFe) through sputtering, forexample, on the insulation layer 102 and has a thickness of 50 to 100nm.

According to the embodiment, although the inner lateral surfaces of theconductive layers 104 do not face the bottom shield layer 103 , theouter lateral surfaces of the conductive layers 104 are shielded by thebottom shield layer 103. As a result, the effects of noises on theconductive layers 104 are sufficiently reduced.

According to the embodiment, the seed layers 131 are provided that areused for forming the conductive layers 104 and electrically connected tothe conductive layers 104. The seed layers 131 are formed in a regionlarger than the region where the conductive layers 104 are formed. As aresult, the wiring resistance of the conductive layers connected to theMR element 108 is more greatly reduced.

As shown in FIG. 32, if the conductive layers 104 form part of a ring,the conductive layers 104 may function as a coil and receive noises. Inthe embodiment, however, the seed layers 131 electrically connected tothe conductive layers 104 are formed in a region larger than the regionwhere the conductive layers 104 are formed. Consequently, the shape ofthe conductor including the conductive layers 104 and the seed layers131 does not form part of a ring. As a result, the influence of noiseson the conductive layers 104 is reduced.

The remainder of configuration, functions and effects of the embodimentare similar to those of the seventh embodiment.

[Eleventh Embodiment]

Reference is now made to FIG. 39 to describe a eleventh embodiment ofthe invention. FIG. 39 is a top view of a thin-film magnetic head of theembodiment. FIG. 39 shows the state before mechanical processing of theslider is performed.

The thin-film magnetic head of the embodiment is similar to that of thetenth embodiment except that the shield layers 121 facing the conductivelayers 104 are further provided as in the eighth embodiment.

The remainder of configuration, functions and effects of the embodimentare similar to those of the eighth or tenth embodiment.

[Twelfth Embodiment]

Reference is now made to FIG. 40A, FIG. 40B and FIG. 41 to describe atwelfth embodiment of the invention. FIG. 40A is a cross section of athin-film magnetic head of the embodiment orthogonal to the air bearingsurface. FIG. 40B is a cross section of the pole portion of thethin-film magnetic head of the embodiment parallel to the air bearingsurface. FIG. 41 is a top view of the thin-film magnetic head. FIG. 40Aand FIG. 41 show the state before mechanical processing of the slider isperformed.

In the thin-film magnetic head of the embodiment, as shown in FIG. 41,the bottom shield layer 103 has a configuration similar to that of thebottom shield layer 103 of the seventh embodiment except that a portionbetween the pair of conductive layers 104 is removed while portionshaving a specific width along the conductive layers 104 are only left.Therefore, in the twelfth embodiment, the bottom shield layer 103 facesthe inner lateral surfaces of the conductive layers 104. The portions ofthe bottom shield layer 103 of the embodiment that face the innerlateral surfaces of the conductive layers 104 have a thickness similarto that of the conductive layers 104, for example. In the embodiment,the shield layers 121 facing the conductive layers 104 are provided asin the eighth embodiment.

The remainder of configuration, functions and effects of the embodimentare similar to those of the eighth embodiment.

[Thirteenth Embodiment]

Reference is now made to FIG. 42 to describe a thirteenth embodiment ofthe invention. FIG. 42 is a top view of a thin-film magnetic head of theembodiment. FIG. 42 shows the state before mechanical processing of theslider is performed.

In the embodiment a bottom shield layer 163 is provided in place of thebottom shield layer 103 of the twelfth embodiment. The entire shape ofthe bottom shield layer 163 is similar to that of the bottom shieldlayer 103 of the twelfth embodiment except that the bottom shield layer163 is divided into a portion 163A facing the MR element 8 and portions163B and 163C not facing the MR element 8. Specific gaps are eachprovided between the portion 163A and the portion 163B and between theportion 163A and the portion 163C. The bottom shield layer 163 hasgrooves 163 a in which portions of the conductive layers 104 are placed,as the grooves 103 a of the bottom shield layer 103 of the seventhembodiment. The portions 163B and 163C are each divided into twoportions by the grooves 163 a . Therefore, the bottom shield layer 163is actually divided into the five portions.

The bottom shield layer 163 and the conductive layers 104 of theembodiment are selectively formed through plating with a photoresistfilm as a mask on part of the seed layer selectively left throughetching, the part of the seed layer corresponding to the bottom shieldlayer 163 and the conductive layers 104.

In the embodiment the shield layers 121 facing the conductive layers 104are provided as in the twelfth embodiment.

According to the embodiment, the bottom shield layer 163 is divided intothe five portions. Therefore, the area of each portion is small and theshield property in a high frequency range is improved.

The remainder of configuration, functions and effects of the embodimentare similar to those of the twelfth embodiment.

In the seventh, eighth, twelfth and thirteenth embodiments one of thetwo shield layers facing each other with the MR element in between hasthe grooves in which at least part of the conductive layers connected tothe MR element is placed. At least part of the conductive layers is madeof the same material as the one of the shield layers. The part of theconductive layers is placed in the grooves, being insulated form theshield layer. As a result, according to the embodiments, the insulationproperty is improved between the conductive layers and each shieldlayer. Furthermore, since the conductive layers are not placed betweenthe shield layers with the insulating layers in between, the insulationproperty is improved between each shield layer and the conductive layersconnected to the MR element without increasing the thickness of theinsulating layer between the MR element and each shield layer. Accordingto the embodiments, it is possible to make the conductive layerssufficiently thick. The wiring resistance of the conductive layers isthereby reduced. According to the embodiments, part of the conductivelayers placed in the grooves is shielded, being held in the middle ofone of the shield layers. The effects of noises on the conductive layersare thereby reduced. According to the embodiments, at least part of theconductive layers is made of the same material as one of the shieldlayers so that these layers may be fabricated in the same manufacturingstep. The number of manufacturing steps of the thin-film magnetic headis therefore reduced.

If the shield layers are provided for shielding at least part of theconductive layers, the effects of noises on the conductive layers arefurther reduced.

The one of the shield layers may be divided into the portion facing theMR element and the portions not facing the MR element. The shieldproperty in a high frequency range is thereby improved.

In the ninth to eleventh embodiments one of the shield layers and atleast part of the conductive layers are made of the same material andplaced in one plane, being insulated from each other. Therefore,according to the embodiments, the insulation property is improvedbetween the conductive layers and each shield layer. Furthermore, sincethe conductive layers are not placed between the shield layers withinsulating layers in between, the insulation property is improvedbetween each shield layer and the conductive layers connected to the MRelement without increasing the thickness of the insulating layer betweenthe MR element and each shield layer. In addition, it is possible tomake the conductive layers sufficiently thick. The wiring resistance ofthe conductive layers is thereby reduced.

According to the ninth to eleventh embodiments, the shield layers areprovided for shielding at least part of the conductive layers. Theeffects of noises on the conductive layers are thereby reduced.According to the tenth and eleventh embodiments, the seed layer isprovided that is used for fabricating at least part of the conductivelayers and formed in the region larger than the region where at leastpart of the conductive layers is formed. The seed layer is electricallyconnected to at least part of the conductive layers. The wiringresistance of the conductive layers is thereby reduced and the effectsof noises on the conductive layers are reduced.

[Fourteenth Embodiment]

Reference is now made to FIG. 43A to FIG. 51A, FIG. 43B to FIG. 51B,FIG. 52 and FIG. 53 to describe a composite thin-film magnetic head anda method of manufacturing the same of a fourteenth embodiment of theinvention. FIG. 43A to FIG. 51A are cross sections each orthogonal tothe air bearing surface of the thin-film magnetic head. FIG. 43B to FIG.51B are cross sections each parallel to the air bearing surface of thepole portion of the head.

In the method of the embodiment, as shown in FIG. 43A and FIG. 43B, aninsulating layer 202 made of alumina (Al₂O₃), for example, of about 5 to10 μn in thickness is deposited on a substrate 201 made of aluminumoxide and titanium carbide (Al₂O₃-TiC), for example.

Although not shown, a seed layer is made on the insulating layer 202through sputtering Permalloy (NiFe). The seed layer is used for forminga bottom shield layer and part of a top shield layer-cum-bottom polelayer (called top shield layer in the following description) throughplating.

Next, as shown in FIG. 44A and FIG. 44B, on the seed layer a magneticmaterial such as Permalloy (NiFe) is selectively deposited to athickness of about 2 to 3 μm through plating with a photoresist film asa mask. A bottom shield layer 203 for the reproducing head and a portion(called a first portion in the following description) 204 a of a topshield layer are thereby formed. Alternatively, the bottom shield layer203 and the first portion 204 a may be formed by sputtering a magneticmaterial and pattering the material through photolithography. The bottomshield layer 203 and the first portion 204 a are formed in one plane,being insulated from each other by the photoresist. Between the bottomshield layer 203 and the first portion 204 a, a pair of grooves 205 areformed in which at least portions of conductive layers to be connectedto an MR element are placed. The bottom shield layer 203 corresponds tothe first shield layer of the invention. The top shield layercorresponds to the second shield layer of the invention.

Next, part of the seed layer that covers the grooves 205 is selectivelyetched and removed. An insulating film 206 of alumina, for example,whose thickness is 500 nm or above is formed through sputtering, forexample, on the bottom shield layer 203 and the first portion 204 a ofthe top shield layer including inside the grooves 205.

Next, as shown in FIG. 45A and FIG. 45B, a pair of conductive layers 207are made of coppers, for example, in the grooves 205 covered with theinsulating film 206. The conductive layers 207 make up leads connectedto the MR element. The conductive layers 207 may be formed by depositingcopper to a thickness of about 2 to 3 μm through plating selectively inthe grooves 205 with a photoresist film as a mask. Alternatively, theconductive layers 207 may be formed through sputtering.

Next, an insulating layer made of alumina or silicon dioxide, forexample, whose thickness is 4 to 6 μm is formed on the entire surface.The insulating layer is then polished to the surfaces of the bottomshield layer 203, the first portion of the top shield layer and theconductive layers 207 and flattened. The polishing method may bemechanical polishing or CMP. Through this flattening process, thesurfaces of the bottom shield layer 203, the first portion 204 a and theconductive layers 207 are exposed.

As thus described, the conductive layers 207 are formed through platingand precisely embedded in the grooves 205 between the bottom shieldlayer 203 and the first portion 204 a of the top shield layer, thegrooves 205 being fully covered with the insulating film 206 of 500 nmor above in thickness. As a result, an extremely high insulationproperty is obtained between the conductive layers 207 and the bottomshield layer 203 and the first portion 204 a. It is therefore possibleto prevent magnetic and electrical insulation faults between theconductive layers 207 and the bottom shield layer 203 and the firstportion 204 a due to particles or pinholes in the layers.

Next, an insulating material such as aluminum nitride or alumina issputtered to a thickness of about 50 to 100 nm over the bottom shieldlayer 203, the first portion 204 a of the top shield layer, theinsulating film 206 and the conductive layers 207. A bottom shield gapfilm 208 a as an insulating layer is thus formed. Before forming thebottom shield gap film 208 a, a photoresist pattern in a T-shape, forexample, is formed to facilitate liftoff where contact holes are to beformed. Some of the contact holes are provided for electricallyconnecting the conductive layers 207 to other conductive layersdescribed later. Another one of the contact hole is provided forconnecting the first portion 204 a to a second portion described laterof the top shield layer. Still another one of the contact hole isprovided for making a magnetic path behind (the right side of FIG. 45A)a thin-film coil described later. After the bottom shield gap film 208 ais formed, the contact holes are formed through lifting off thephotoresist patterns. Alternatively, the contact holes may be formed byselectively etching the bottom shield gap film 208 a through the use ofphotolithography.

Next, an MR film of tens of nanometers in thickness for forming an MRelement 209 for reproduction is deposited through sputtering on thebottom shield gap film 208 a. A photoresist pattern (not shown) is thenselectively formed where the MR element 209 is to be formed on the MRfilm. The photoresist pattern may be T-shaped, for example, tofacilitate liftoff. Next, the MR film is etched through argon-base ionmilling, for example, with the photoresist pattern as a mask to form theMR element 209. The MR element 209 may be either a GMR element or an AMRelement.

Next, on the bottom shield gap film 208 a, a pair of conductive layers210 of 80 to 150 nm in thickness are formed through sputtering with thesame photoresist pattern as a mask. The conductive layers 210 are to beelectrically connected to the MR element 209. The conductive layers 210may be formed through stacking TiW, CoPt, TiW, Ta, and Au, for example.The conductive layers 210 are electrically connected to the conductivelayers 207 through the contact holes provided in the bottom shield gapfilm 208 a. The conductive layers 210 and 207 make up the leadsconnected to the MR element 209.

Next, on the bottom shield gap film 208 a, the MR element 209 and theconductive layers 210, an insulating material such as aluminum nitrideor alumina is sputtered to a thickness of about 50 to 100 nm to form atop shield gap film 208 b as an insulating layer. The MR element 209 isthus embedded in the shield gap films 208 a and 208 b.

Next, an insulating film made of alumina or silicon dioxide, forexample, whose thickness is 1 to 2 μm is formed behind the contact holeprovided in the bottom shield gap film 208 a (that is, the right side ofFIG. 45A) on the bottom shield gap film 208 a. The insulating film isthen selectively etched through photolithography to form an insulatinglayer 211. The edge of the insulating layer 211 close to the poleportion is tapered. Next, a thin-film coil 212 of a first layer for therecording head is made of copper, for example, through plating, forexample.

Next, as shown in FIG. 46A and FIG. 46B, a second portion 204 b of thetop shield layer is formed on the top shield gap film 208 b. The secondportion 204 b is made of a magnetic material and has a thickness of 2 to3 μm and is connected to the first portion 204 a of the top shieldlayer. The second portion 204 b is placed to face the bottom shieldlayer 203 with the MR element 209 in between. At the same time, amagnetic layer 213 for making the magnetic path is formed on the contacthole for making the magnetic path behind the thin-film coil 212. Themagnetic layer 213 is made of a magnetic material and has a thickness of2 to 3 μm.

The bottom shield layer 203 and the top shield layer 204 a and 204 b maybe made of NiFe (80 weight % Ni and 20 weight % Fe) or a high saturationflux density material such as NiFe (50 weight % Ni and 50 weight % Fe),Sendust, FeN or a compound thereof, or an amorphous of Fe—Co—Zr. Thebottom shield layer 203 and the top shield layer 204 a and 204 b may bemade of layers of two or more of those materials.

Next, as shown in FIG. 47A and FIG. 47B, an alumina film or a silicondioxide film of 4 to 6 μm in thickness is formed over the entiresurface. The entire surface is then flattened so that the surfaces ofthe second portion 204 b of the top shield layer and the magnetic layer213 are exposed. The flattening may be performed through mechanicalpolishing or CMP. Such a flattening process prevents formation of a risein the second portion 204 b of the top shield layer caused by thepattern of the MR element 209. The surface of the second portion 204 bis thus made flat, and a recording gap layer of the magnetic pole of therecording head to be formed is made flat. As a result, the writingproperty in a high frequency range is improved.

Next, as shown in FIG. 48A and FIG. 48B, an insulating film 215 ofalumina or silicon dioxide of 0.5 to 1 μm in thickness is formed on theflattened second portion 204 b of the top shield layer and theinsulating layer 214. The insulating film 215 defines the throat height.On the insulating film 215 a thin-film coil 216 of a second layer of therecording head is formed through plating. The thin-film coil 216 may bemade of copper, for example.

Next, as shown in FIG. 49A and FIG. 49B, as insulating layer 217 made ofphotoresist is formed into a specific pattern on the insulating layer215 and the coil 216. A recording gap layer 218 of 200 to 300 nm inthickness made of an insulating film of alumina, aluminum nitride, orsilicon dioxide, for example, is formed on the entire surface.

Next, as shown in FIG. 50A and FIG. 50B, the recording gap layer 218 isthen partially etched to form the magnetic path behind the thin-filmcoils 212 and 216. Next, a top pole layer 219 of about 3 μm in thicknessis formed on the recording gap layer 218. The top pole layer 219determines the track width of the induction recording head. The top polelayer 219 may be formed through plating with NiFe (50 weight % Ni and 50weight % Fe), or through sputtering a high saturation flux densitymaterial such as FeN or a compound thereof and then patterning. Besidesthe above examples, the material of the top pole layer 219 may be a highsaturation flux density material such as NiFe (80 weight % Ni and 20weight % Fe) or an amorphous of Fe—Co—Zr. Alternatively, the top polelayer 219 may be layers of two or more of the above materials.

Next, as shown in FIG. 51A and FIG. 51B, part of the recording gap layer218 on both sides of the top pole layer 219 is removed through dryetching. The exposed second portion 204 b of the top shield layer isthen etched through ion milling by about 0.5 μm, for example, with thetop pole layer 219 as a mask so as to form a trim structure.

Next, an overcoat layer 220 of alumina, for example, whose thickness isabout 30 to 40 μm is formed to cover the top pole layer 219. Finally,machine processing of the slider is performed and the air bearingsurface of the recording head and the reproducing head is formed. Thethin-film magnetic head is thus completed.

The top shield layer (bottom pole layer) 204 a and 204 b, the magneticlayer 213, the top pole layer 219, and the thin-film coils 212 and 216correspond to the induction-type magnetic transducer of the invention.That is, the top shield layer (bottom pole layer) 204 a and 204 b andthe magnetic layer 213 correspond to one of the two magnetic layers ofthe recording head of the invention. The top pole layer 219 correspondsto the other of the two magnetic layers.

FIG. 52 is a top view of the thin-film magnetic head of the embodimentmanufactured through the foregoing process in the state in one of themanufacturing steps. FIG. 53 is a top view of the thin-film magnetichead of the embodiment manufactured through the foregoing process. FIG.52 correspond to the state shown in FIG. 45A and FIG. 45B. In FIG. 53the overcoat layer 220 is omitted. FIG. 53 shows the state beforemechanical processing of the slider is performed. FIG. 43A to FIG. 51Aare cross sections taken along line 51A—51A of FIG. 53. FIG. 43B to FIG.51B are cross sections taken along line 51B-51B of FIG. 53.

As shown in FIG. 52 and FIG. 53, the bottom shield layer 203 extendsfrom the regions facing the MR element 209 and their periphery to sidesof the MR element 209. Portions of the bottom shield layer 203 passthrough the regions facing the second region 204 b of the top shieldlayer. Most of the remaining portions are placed around the regionfacing the two magnetic layers (the top shield layer 204 a and 204 b andthe magnetic layers 213; and the top pole layer 219) of theinduction-type magnetic transducer and the thin-film coils 212 and 216.

The bottom shield layer 203 and the first portion 204 a of the topshield layer are placed in one plane, being insulated from each other.The grooves 205 are provided between the bottom shield layer 203 and thefirst portion 204 a. Portions of the conductive layers 207 making up theleads connected to the MR element 209 that are close to the MR element209 are placed in the grooves 205, being insulated. The remainingportions of the conductive layers 207 are placed along the inner lateralsurface of the bottom shield layer 203, being insulated from the bottomshield layer 203.

In the embodiment, the bottom shield layer 203 and the first portion 204a of the top shield layer are placed in one plane, being insulated fromeach other. Portions of the conductive layers 207 making up the leadsconnected to the MR element 209 are placed in the grooves 205 providedbetween the bottom shield layer 203 and the first portion 204 a, theportions of the conductive layers 207 being insulated by the insulatingfilm 206 from the bottom shield layer 203 and the first portion 204 a.As a result, according to the embodiment, an extremely high insulationproperty is achieved between the conductive layers 207 and the bottomshield layer 203 and the first portion 204 a of the top shield layer.Although part of the conductive layers 207 faces the second portion 204b of the top shield layer with the bottom shield gap film 208 a and thetop shield gap film 208 b in between, the most part of the conductivelayers 207 does not face the top shield layer 204 a and 204 b. Anextremely high insulation property is therefore achieved between theconductive layers 207 and the top shield layer 204 a and 204 b.

According to the embodiment, as thus described, an extremely highinsulation property is achieved between the conductive layers 207 andthe bottom shield layer 203 and the top shield layer 204 a and 204 b. Itis therefore possible to prevent magnetic and electrical insulationfaults between the conductive layers 207 and the bottom shield layer 203and the top shield layer 204 a and 204 b.

According to the embodiment, the conductive layers 207 are not insertedbetween the bottom shield gap film 208 a and the top shield gap film 208b. As a result, it is impossible that large areas of the conductivelayers 207 face the bottom shield layer 203 and the top shield layer 204a and 204 b with the bottom shield gap film 208 a and the top shield gapfilm 208 b in between. Therefore, although the bottom shield gap film208 a and the top shield gap film 208 b are thin, the insulationproperty is maintained at a high level between the conductive layers 207and the bottom shield layer 203 and between the conductive layers 207and the top shield layer 204 a and 204 b.

According to the embodiment described so far, the insulation property isimproved between the conductive layers connected to the MR element 209and the bottom shield layer 203 and between the conductive layers andthe top shield layer 204 a and 204 b without increasing the thickness ofthe bottom shield gap film 208 a and the top shield gap film 208 b.

According to the embodiment, the bottom shield gap film 208 a and thetop shield gap film 208 b are made thin enough to improve the thermalasperity. The property of the reproducing head is thereby improved.

According to the embodiment, the conductive layers 207 are made thickenough so that the wiring resistance of the conductive layers connectedto the MR element 209 is more greatly reduced. As a result, it ispossible to detect with sensitivity a minute change in the output signalcorresponding to a minute change in resistance of the MR element 209.The property of the reproducing head is improved in this respect, too.

In the embodiment, the lateral surfaces of the portions of theconductive layers 207 close to the MR element 209 and placed in thegrooves 205 are shielded, being placed between the bottom shield layer203 and the first portion 204 a of the top shield layer. The topsurfaces of the portions of the conductive layers 207 are shielded bythe second portion 204 b of the top shield layer. As a result, it ispossible to reduce the effects of noises caused by internal factors suchas magnetism and the like generated by the coil of the induction-typerecording head or external factors such as the motor of the hard diskdrive. The property of the reproducing head is improved in this respect,too.

According to the embodiment, the thin-film coil 216 of the first layeris placed between the first portion 204 a of the top shield layer andthe top pole layer 219, and placed next to the second portion 204 b ofthe top shield layer, being parallel to the surfaces of the secondportion 204 b. As a result, the height of the apex, that is, the crestof the coil, is reduced and the pole layer (the top pole layer 219) thatdefines the track width of the recording head is reduced in size. Therecording density is thereby increased and the recording head propertyis improved.

According to the embodiment, the thick insulating layer 211 is formedbetween the coils 212 and 216 and the first portion 204 a of the topshield layer. As a result, a high insulation strength is achievedbetween the coils 212 and 216 and the top shield layer 204 a and 204 b.Magnetic flux leakage from the coils 212 and 216 is reduced as well.

[Fifteenth Embodiment]

Reference is now made to FIG. 54 to describe a fifteenth embodiment ofthe invention. FIG. 54 is a top view of a thin-film magnetic head of theembodiment. The overcoat layer is omitted in FIG. 54. FIG. 54 shows thestate before mechanical processing of the slider is performed.

The thin-film magnetic head of the embodiment includes shield layers 221for shielding at least portions of the conductive layers 207. The shieldlayers 221 cover the portions of the conductive layers 207 that do notface the second portion 204 b of the top shield layer. Where theinsulating layer 211 is provided, the shield layers 221 are formed onthe insulating layer 211. The shield layers 221 are formed on the bottomshield gap film 208 a where the insulating layer 211 is not provided.

In the step of making the top pole layer 219, the shield layers 221 maybe formed at the same time through the use of the same magneticmaterial.

According to the embodiment, the shield layers 221 shield the topsurfaces of the portions of the conductive layers 207 that do not facethe second portion 204 b of the top shield layer. As a result, theeffects of noises on the conductive layers 207 are more greatly reduced,compared to the fourteenth embodiment.

The remainder of configuration, functions and effects of the embodimentare similar to those of the fourteenth embodiment.

[Sixteenth Embodiment]

Reference is now made to FIG. 55A to FIG. 60A, FIG. 55B to FIG. 60B,FIG. 61 and FIG. 62 to describe a composite thin-film magnetic head anda method of manufacturing the same of a sixteenth embodiment of theinvention. FIG. 55A to FIG. 60A are cross sections each orthogonal tothe air bearing surface of the thin-film magnetic head. FIG. 55B to FIG.60B are cross sections each parallel to the air bearing surface of thepole portion of the head.

In the method of the embodiment, as shown in FIG. 55A and FIG. 55B, aninsulating layer 252 made of alumina (Al₂O₃), for example, of about 5 to10 μm in thickness is deposited on a substrate 251 made of aluminumoxide and titanium carbide (Al₂O₃-TiC), for example.

Although not shown, a seed layer is made on the insulating layer 252through sputtering Permalloy (NiFe). The seed layer is used for forminga bottom shield layer and part of a top shield layer-cum-bottom polelayer (called top shield layer in the following description) throughplating.

Next, as shown in FIG. 56A and FIG. 56B, on the seed layer a magneticmaterial such as Permalloy (NiFe) is selectively deposited to athickness of about 2 to 3 μm through plating with a photoresist film asa mask. A bottom shield layer 253 for the reproducing head and a portion(called a first portion in the following description) 254 a of a topshield layer are thereby formed. Alternatively, the bottom shield layer253 and the first portion 254 a may be formed by sputtering a magneticmaterial and pattering the material through photolithography. The bottomshield layer 253 and the first portion 254 a are formed in one plane,being insulated from each other by the photoresist. Between the bottomshield layer 253 and the first portion 254 a, a pair of grooves 255 areformed in which at least portions of conductive layers to be connectedto an MR element are placed. The bottom shield layer 253 corresponds tothe first shield layer of the invention. The top shield layercorresponds to the second shield layer of the invention.

Next, part of the seed layer that covers the grooves 255 is selectivelyetched and removed. An insulating film 256 of alumina, for example,whose thickness is about 0.5 to 1 μm is formed through sputtering, forexample, on the bottom shield layer 253 and the first portion 254 a ofthe top shield layer including inside the grooves 255.

Next, as shown in FIG. 57A and FIG. 55B, a pair of conductive layers 257are made of coppers, for example, in the grooves 255 covered with theinsulating film 256. The conductive layers 257 make up leads connectedto the MR element. The conductive layers 257 may be formed by depositingcopper to a thickness of about 3 μm through plating selectively in thegrooves 255 with a photoresist film as a mask. Alternatively, theconductive layers 257 may be formed through sputtering.

Next, an insulating layer whose thickness is 2 to 3 μm made of aluminaor silicon dioxide, for example, is formed on the entire surface. Theinsulating layer is then polished to the surfaces of the bottom shieldlayer 253, the first portion 254 a of the top shield layer and theconductive layers 257 and flattened. The polishing method may bemechanical polishing or CMP. Through this flattening process, thesurfaces of the bottom shield layer 253, the first portion 254 a and theconductive layers 257 are exposed.

As thus described, the conductive layers 257 are formed through platingand precisely embedded in the grooves 255 between the bottom shieldlayer 253 and the first portion 254 a of the top shield layer, thegrooves 255 being fully covered with the insulating film 256 of 500 nmor above in thickness. As a result, an extremely high insulationproperty is obtained between the conductive layers 257 and the bottomshield layer 253 and the first portion 254 a. It is therefore possibleto prevent magnetic and electrical insulation faults between theconductive layers 257 and the bottom shield layer 253 and the firstportion 254 a due to particles or pinholes in the layers.

Next, an insulating film of alumina or silicon dioxide having athickness of 0.5 to 1 μm is formed on the first portion 254 a of the topshield layer. The insulating film is selectively etched throughphotolithography to form an insulating layer 258. The edge of theinsulating layer 258 close to the pole portion is tapered. Next, athin-film coil 259 for the recording head is made of copper, forexample, through plating, for example, on the insulating layer 58. Aninsulating layer 260 of photoresist is formed into a specific pattern onthe insulating layer 258 and the coil 259. The entire structure is thencured at a temperature of about 200° C.

Next, as shown in FIG. 58A and FIG. 58B, an insulating material such asaluminum nitride or alumina is sputtered to tens of nanometers over theentire surface to form a bottom shield gap film 261 a. Before formingthe bottom shield gap film 261 a, a photoresist pattern in a T-shape,for example, is formed to facilitate liftoff where contact holes are tobe formed for electrically connecting the conductive layers 257 to otherconductive layers described later. After the bottom shield gap film 261a is formed, the contact holes are formed through lifting off thephotoresist pattern. Alternatively, the contact holes may be formed byselectively etching the bottom shield gap film 261 a through the use ofphotolithography.

Next, an MR film of tens of nanometers in thickness for forming an MRelement 262 for reproduction is deposited through sputtering on thebottom shield gap film 261 a. A photoresist pattern (not shown) is thenselectively formed where the MR element 262 is to be formed on the MRfilm. The photoresist pattern may be T-shaped, for example, tofacilitate liftoff. Next, the MR film is etched through argon-base ionmilling, for example, with the photoresist pattern as a mask to form theMR element 262. The MR element 262 may be either a GMR element or an AMRelement.

Next, on the bottom shield gap film 261 a, a pair of conductive layers263 of tens to hundreds of nanometers in thickness are formed throughsputtering with the same photoresist pattern as a mask. The conductivelayers 263 are to be electrically connected to the MR element 262. Theconductive layers 263 may be formed through stacking TiW, CoPt, TiW, Ta,and Au, for example. The conductive layers 263 are electricallyconnected to the conductive layers 257 through the contact holesprovided in the bottom shield gap film 261 a. The conductive layers 263and 257 make up the leads connected to the MR element 262.

Next, an insulating material such as aluminum nitride or alumina issputtered to a thickness of tens of nanometers to form a top shield gapfilm 261 b as an insulating layer. The MR element 262 is thus embeddedin the shield gap films 261 a and 261 b. Next, the shield gap films 261a and 261 b are selectively removed through dry etching with aphotoresist pattern as a mask. A contact hole is thereby formed forconnecting the first portion 254 a to a second portion described laterof the top shield layer. Another contact hole is thereby formed formaking a magnetic path behind the coil 259 (that is, the right side ofFIG. 58A).

Next, as shown in FIG. 59A and FIG. 59B, a second portion 254 b of thetop shield layer is formed on the side of the pole portion. The secondportion 254 b is made of a magnetic material and has a thickness ofabout 3.5 μm, for example, and is connected to the first portion 254 aof the top shield layer. The second portion 254 b is placed to face thebottom shield layer 253 with the MR element 262 in between. At the sametime, a magnetic layer 264 for making the magnetic path is formed on thecontact hole for making the magnetic path behind the thin-film coil 259.The magnetic layer 264 is made of a magnetic material and has athickness of about 3.5 μm, for example. The second portion 254 a of thetop shield layer and the magnetic layer 264 are formed through plating,for example.

The bottom shield layer 253 and the top shield layer 254 a and 254 b maybe made of NiFe (80 weight % Ni and 20 weight % Fe) or a high saturationflux density material such as NiFe (50 weight % Ni and 50 weight % Fe),Sendust, FeN or a compound thereof, or an amorphous of Fe—Co—Zr. Thebottom shield layer 253 and the top shield layer 254 a and 254 b may bemade of layers of two or more of those materials. Through the use of ahigh saturation flux density material for the bottom shield layer 253and the top shield layer 254 a and 254 b, it is possible to reduce theeffects of noises on the MR element 262 caused by internal factors suchas magnetism and the like generated by the coil of the induction-typerecording head or external factors such as the motor of the hard diskdrive. A precise reproducing output is therefore achieved and a highlysensitive reproducing head is obtained.

Next, as shown in FIG. 60A and FIG. 60B, an insulating layer 265 ofphotoresist is formed into a specific pattern over the coil 259. Theentire structure is then cured at a temperature of about 200° C. Thethroat height is defined by the insulating layer 265 in the embodiment.Next, a recording gap layer 266 of about 300 nm in thickness made of aninsulating film of alumina, aluminum nitride, or silicon dioxide, forexample, is formed on the entire surface. The recording gap layer 266 onthe top surface of the magnetic layer 264 is then partially etched toform a contact hole for making the magnetic path.

Next, a top pole layer 267 of about 3 to 4 μm in thickness is formed onthe recording gap layer 266. The top pole layer 267 determines the trackwidth of the induction recording head. The top pole layer 267 may beformed through plating with NiFe (50 weight % Ni and 50 weight % Fe), orthrough sputtering a high saturation flux density material such as FeNor a compound thereof and then patterning. Besides the above examples,the material of the top pole layer 267 may be NiFe (80 weight % Ni and20 weight % Fe) or a high saturation flux density material such as anamorphous of Fe—Co—Zr. Alternatively, the top pole layer 267 may belayers of two or more of the above materials. The top pole layer 267made of a high saturation flux density material allows the magnetic fluxgenerated by the coil 259 to effectively reach the pole portion withoutsaturating before reaching the pole. A recording head that achieves highrecording density is therefore obtained.

Next, part of the recording gap layer 266 on both sides of the top polelayer 267 is removed through dry etching. The exposed second portion 254b of the top shield layer is then etched through ion milling by about0.5 μm, for example, with the top pole layer 267 as a mask so as to forma trim structure.

Next, an overcoat layer 268 of alumina, for example, whose thickness isabout 30 to 40 μm is formed to cover the top pole layer 267. Finally,machine processing of the slider is performed and the air bearingsurface of the recording head and the reproducing head is formed. Thethin-film magnetic head is thus completed.

The top shield layer (bottom pole layer) 254 a and 254 b, the magneticlayer 264, the top pole layer 267, and the thin-film coil 259 correspondto the induction-type magnetic transducer of the invention. That is, thetop shield layer (bottom pole layer) 254 a and 254 b and the magneticlayer 264 correspond to one of the two magnetic layers of the recordinghead of the invention. The top pole layer 267 corresponds to the otherof the two magnetic layers.

FIG. 61 is a top view of the thin-film magnetic head of the embodimentmanufactured through the foregoing process in the state in one of themanufacturing steps. FIG. 62 is a top view of the thin-film magnetichead of the embodiment manufactured through the foregoing process. FIG.61 corresponds to the state shown in FIG. 57A and FIG. 57B. In FIG. 62the overcoat layer 268 is omitted. FIG. 62 shows the state beforemechanical processing of the slider is performed. Numeral 269 of FIG. 62indicates the contact hole for connecting the second portion 254 b tothe first portion 254 a of the top shield layer. FIG. 55A to FIG. 60Aare cross sections taken along line 60A—60A of FIG. 62. FIG. 55B to FIG.60B are cross sections taken along line 60B—60B of FIG. 62.

As shown in FIG. 62, in this embodiment, too, as in the fifteenthembodiment, shield layers 271 may be provided for shielding at leastportions of the conductive layers 257. The shield layers 271 coverportions of the conductive layers 257 that do not face the secondportion 254 b of the top shield layer. In the step of forming the toppole layer 267, for example, the shield layers 271 may be made of thesame material as the top pole layer 267 at the same time.

As in the fourteenth embodiment, the bottom shield layer 253 and thefirst portion 254 a of the top shield layer are placed in one plane,being insulated from each other. The portions of the conductive layers257 making up the leads connected to the MR element 262 are placed inthe grooves 255 provided between the bottom shield layer 253 and thefirst portion 254 a, being insulated by the insulating film 256 from thebottom shield layer 253 and the first portion 254 a. As a result, theembodiment provides the effects similar to those of the fourteenthembodiment.

Many customers of thin-film magnetic heads order the track width of areproducing head and the throat height and the track width of arecording head that suit their own products. However, if thin-filmmagnetic heads that meet the specifications a customer requires aremanufactured after an order is received, it is difficult to supply theproducts in a short time after the receipt of the order.

According to the embodiment, as shown in FIG. 57A and FIG. 57B, thecommon base body of the thin-film magnetic head is completed in the stepof forming the coil 259 (the formation of the insulating layer 260 inthe embodiment). Therefore, according to the embodiment, theintermediate product having gone through the manufacturing steps as faras the step of forming the coil 259 may be mass-produced so that manyintermediate products in stock are obtained. Such intermediate productsin stock having been increased so that they are plentiful enough to besupplied to customers, the specifications of the thin-film magneticheads may be determined to meet different customers' demands. Therefore,the embodiment allows the appropriate number of intermediate products instock to be obtained. Such intermediate products have gone through 50 to60 percent of the entire manufacturing steps and many of them havepassed an inspection as conforming products. It is therefore possible toproduce thin-film magnetic heads that meet the specifications requiredby the customer in a short time after receipt of an order. According tothe embodiment, noncorfoming intermediate products have been alreadyeliminated so that it is possible to make conforming intermediateproducts into complete products as soon as possible in accordance withcustomers' demands. High quality of the products is therefore achievedand the yields of the finished products improve.

The remainder of configuration, functions and effects of the embodimentare similar to those of the fourteenth or fifteenth embodiment.

[Seventeenth Embodiment]

Reference is now made to FIG. 63A and FIG. 63B to describe a seventeenthembodiment of the invention. FIG. 63A is a cross section of a thin-filmmagnetic head of the embodiment orthogonal to the air bearing surface.FIG. 63B is a cross section of the pole portion of the thin-filmmagnetic head parallel to the air bearing surface. FIG. 63A shows thestate before mechanical processing of the slider is performed.

In the thin-film magnetic head of the embodiment, a thin-film coil 272of a second layer is formed in the insulating layer 265 made ofphotoresist of the thin-film magnetic head of the sixteenth embodiment.In this case, the insulating layer 265 of photoresist having a specificthickness is formed over the coil 259. The coil 272 is then formedthrough plating, for example. The insulating layer 265 is further formedto cover the coil 272. The throat height is defined by the insulatinglayer 265 in the embodiment.

The remainder of configuration, functions and effects of the embodimentare similar to those of the sixteenth embodiment.

[Eighteenth Embodiment]

Reference is now made to FIG. 64A to FIG. 66A, FIG. 64B to FIG. 66B,FIG. 67 and FIG. 68 to describe a composite thin-film magnetic head anda method of manufacturing the same of an eighteenth embodiment of theinvention. FIG. 64A to FIG. 66A are cross sections each orthogonal tothe air bearing surface of the thin-film magnetic head. FIG. 64B to FIG.66B are cross sections each parallel to the air bearing surface of thepole portion of the head. The method of manufacturing the thin-filmmagnetic head of the embodiment is similar to that of the sixteenthembodiment as far as the step of forming the coil 259. The intermediateproducts having reached the step are mass-produced and gone through aninspection. An appropriate amount of conforming intermediate productsare obtained.

In this embodiment, in order to complete the product to meet thecustomer's demands, the MR element (an AMR element or a GMR element, andso on) and the material of the shield gap film (alumina, aluminumnitride or boron nitride and so on) are selected and the track width ofthe reproducing head and the throat height and the track width of therecording head are determined in accordance with the customer'srequests. As shown in FIG. 64A and FIG. 64B, the shield gap films 261 aand 261 b, the MR element 262 and the conductive layers 263 are thenformed. Next, the second portion 254 b of the top shield layer and themagnetic layer 264 are formed. An insulating layer 281 of alumina, forexample, having a thickness of 3 to 4 μm is then formed over the entiresurface. The entire surface is then polished through CMP, for example,so that the surfaces of the second portion 254 b and the magnetic layer264 are exposed.

Next, as shown in FIG. 65A and FIG. 65B, on the second portion 254 b ofthe top shield layer and the insulating layer 281, an insulating layer282 of alumina, for example, that defines the throat height of therecording head is formed. Next, a thin-film coil 283 of a second layeris formed on the insulating layer 282. An insulating layer 284 ofphotoresist is then formed into a specific pattern on the insulatinglayer 282 and the coil 283. Next, a recording gap layer 285 made of aninsulating film of alumina, for example, is formed. The portion of therecording gap layer 285 on the magnetic layer 264 is then selectivelyremoved to form a contact hole for making a magnetic path.

Next, as shown in FIG. 66A and FIG. 66B, a top pole layer 286 is formedon the recording gap layer 285. The top pole layer 286 defines the trackwidth of the induction-type recording head. Next, the recording gaplayer 285 on sides of the top pole layer 286 is removed through dryetching such as reactive ion etching. The exposed second portion 254 bof the top shield layer is etched through ion milling and the like withthe top pole layer 286 as a mask. A trim structure is thereby formed.

Next, an overcoat layer 287 of alumina, for example, whose thickness isabout 3 to 5 μm is formed to cover the top pole layer 286. Finally,machine processing of the slider is performed and the air bearingsurface of the recording head and the reproducing head is formed. Thethin-film magnetic head is thus completed.

FIG. 67 is a top view of the thin-film magnetic head of the embodimentmanufactured through the foregoing process in the state in one of themanufacturing steps. In the embodiment, as shown in FIG. 67, the firstportion 254 a of the top shield layer is provided in the regioncorresponding to the entire coil 259.

FIG. 68 is a top view of the thin-film magnetic head of the embodimentmanufactured through the foregoing process. In FIG. 68 the overcoatlayer 287 is omitted. FIG. 68 shows the state before mechanicalprocessing of the slider is performed. Numeral 269 of FIG. 68 indicatesthe contact hole for connecting the second portion 254 b to the firstportion 254 a of the top shield layer. FIG. 64A to FIG. 66A are crosssections taken along line 66A—66A of FIG. 68. FIG. 64B to FIG. 66B arecross sections taken along line 66B—66B of FIG. 68.

As shown in FIG. 68, in this embodiment, too, as in the fifteenthembodiment, the shield layers 271 may be provided for shielding at leastportions of the conductive layers 257. The shield layers 271 cover theportions of the conductive layers 257 that do not face the secondportion 254 b of the top shield layer. In the step of forming the toppole layer 286, for example, the shield layers 271 may be made of thesame material as the top pole layer 286 at the same time.

The remainder of configuration, functions and effects of the embodimentare similar to those of the sixteenth embodiment.

In the fourteenth to eighteenth embodiments the first shield layer andpart of the second shield layer are formed in one plane. At leastportions of the conductive layers connected to the MR element are placedin the grooves provided between the first shield layer and part of thesecond shield layer, being insulated form the first and second shieldlayers. As a result, according to the embodiments, the insulationproperty is improved between the conductive layers and each shieldlayer. Furthermore, since the conductive layers are not placed betweenthe shield layers with insulating layers in between, the insulationproperty is improved between each shield layer and the conductive layersconnected to the MR element without increasing the thickness of theinsulating layer between the MR element and each shield layer. Accordingto the embodiments, it is possible to make the conductive layerssufficiently thick. The wiring resistance of the conductive layers isthereby reduced. According to the embodiments, the portions of theconductive layers placed in the grooves are shielded, being placedbetween the shield layers. The effects of noises on the conductivelayers are thereby reduced.

The second shield layer may also function as one of the two magneticlayers of the induction magnetic transducer for writing. At the sametime, at least part of the thin-film coil may be placed between thefirst portion of the second shield layer and the other of the twomagnetic layers, and placed next to the second portion of the secondshield layer, being parallel to the surfaces of the second portion. Inthis case the height of the crest of the coil is reduced and the polethat defines the track width of the recording head is reduced in size.

If the shield layers are provided for shielding at least portions of theconductive layers, the effects of noises on the conductive layers arefurther reduced.

[Nineteenth Embodiment]

Reference is now made to FIG. 69A to FIG. 80A, FIG. 69B to FIG. 80B,FIG. 81 and FIG. 82 to describe a composite thin-film magnetic head anda method of manufacturing the same of a nineteenth embodiment of theinvention. FIG. 69A to FIG. 80A are cross sections each orthogonal tothe air bearing surface of the thin-film magnetic head. FIG. 69B to FIG.80B are cross sections each parallel to the air bearing surface of thepole portion of the head. The following description applies to amagnetic head material and a method of manufacturing the same of theembodiment as well.

In the method of the embodiment, as shown in FIG. 69A and FIG. 69B, aninsulating layer 302 made of alumina (Al₂O₃), for example, of about 10μm in thickness is deposited on a substrate 301 made of aluminum oxideand titanium carbide (Al₂O₃-TiC), for example. The substrate 301 and theinsulating layer 302 correspond to a base body of the invention.

Next, as shown in FIG. 70A and FIG. 70B, a metal mask 303 of a specificpattern is formed on the insulating layer 302 to form a concave in theinsulating layer 302. The metal mask 303 may be made of Permalloy (NiFe)through plating. The insulating layer 302 is then etched by about 7 to 8μm through dry etching such as reactive ion etching with the metal mask303 as a mask to form a concave 304. An etching gas used for reactiveion etching may be any of BCl₃, Cl₂, CF₄, SF₆ and so on. In theembodiment, the angle of the pole-portion-side slope 304 a of theconcave 304 defines the apex angle that influences the property of therecording head. The angle of the slope 304 a is defined by the etchingprofile of the insulating layer 302. The angle of the slope 304 a ispreferably 45 to 70 degrees.

The concave 304 is formed into the shape of a ring where a thin-filmcoil described later will be placed. Therefore, in the insulating layer302, an insular portion 304 b surrounded by the concave 304 is formed.

Next, as shown in FIG. 71A and FIG. 71B, the metal mask 303 is removed.Next, although not shown, a seed layer is made on the insulating layer302 through sputtering Permalloy (NiFe). The seed layer is used forforming a bottom shield layer and part of a top shield layer-cum-bottompole layer (called top shield layer in the following description)through plating.

Next, as shown in FIG. 72A and FIG. 72B, on the seed layer a magneticmaterial such as Permalloy (NiFe) is selectively deposited to athickness of about 2 to 4 μm through plating with a photoresist film asa mask. A bottom shield layer 305 for the reproducing head and a portion(called a first portion in the following description) 306 a of a topshield layer are thereby formed at the same time in one manufacturingstep.

On the insulating layer 302 the bottom shield layer 305 is placed in theportion including at least the pole portion except the concave 304. Onthe insulating layer 302 the first portion 306 a of the top shield layeris placed along the inner surface of the concave 304 and outside theconcave 304 around the edge of the concave 304 and on the insularportion 304 b. A pair of grooves 307 are formed between the bottomshield layer 305 and the first portion 306 a of the top shield layer. Inthe grooves 307 at least portions of a pair of conductive layers to beconnected to an MR element are to be placed. The seed layer in thegrooves is removed by dry etching such as ion milling so as toelectrically and magnetically insulate the bottom shield layer 305 fromthe first portion 306 a. Alternatively, the bottom shield layer 305 andthe first portion 306 a may be formed by sputtering a magnetic materialover the entire surface of the insulating layer 302 and performing dryetching such as argon-base ion milling with a photoresist film as amask. The bottom shield layer 305 corresponds to the first shield layerof the invention. The top shield layer corresponds to the second shieldlayer of the invention.

Next, as shown in FIG. 73A and FIG. 73B, an insulating film 308 ofalumina, for example, whose thickness is about 0.5 to 1 μm is formedthrough sputtering, for example, on the bottom shield layer 305 and thefirst portion 306 a of the top shield layer including inside the grooves307. Next, in one manufacturing step through the use of the samematerial such as copper, for example, a pair of conductive layers 309 tomake up leads connected to the MR element are made in the grooves 307covered with the insulating film 308 and a thin-film coil 310 of a firstlayer for the recording head is formed on the insulating layer 308 inthe concave 304. The conductive layers 309 and the coil 310 may beformed by plating copper with a photoresist film as a mask.Alternatively, the conductive layers 309 and the coil 310 may be formedthrough sputtering.

As thus described, the conductive layers 309 are formed through platingand precisely embedded in the grooves 307 between the bottom shieldlayer 305 and the first portion 306 a of the top shield layer, thegrooves 307 being fully covered with the insulating film 308 of 500 nmor above in thickness. As a result, an extremely high insulationproperty is obtained between the conductive layers 309 and the bottomshield layer 305 and the first portion 306 a. It is therefore possibleto prevent magnetic and electrical insulation faults between theconductive layers 309 and the bottom shield layer 305 and the firstportion 306 a due to particles or pinholes in the layers.

Next, an insulating layer 311 made of photoresist is formed on theinsulating film 308 and the coil 310 in the concave 304. Next, athin-film coil 312 of a second layer is formed on the insulating layer311 in the concave 304. The coil 312 may be made of copper throughplating with a photoresist film as a mask. Alternatively, the coil 312may be formed through sputtering. Next, an insulating layer 313 ofphotoresist is formed on the insulating layer 311 and the coil 312 inthe concave 304. The entire structure is then annealed at a temperatureof about 200 to 250° C.

Although the conductive layers 309 are formed at the same time as thethin-film coil 310 of the first layer in the above description, theconductive layers 309 may be formed at the same time as the thin-filmcoil 312 of the second layer.

Next, as shown in FIG. 74A and FIG. 74B, an insulating layer 314 ofalumina or silicon dioxide, for example, whose thickness is about 3 to 4μm is formed on the entire surface.

Next, as shown in FIG. 75A and FIG. 75B, the insulating layer 314 andthe insulating film 308 below are then polished to the surfaces of thebottom shield layer 305, the first portion 306 a of the top shieldlayer, the conductive layers 309 and part (not shown) of the coil 312and flattened. The polishing method may be mechanical polishing or CMP.Through this flattening process, the surfaces of the bottom shield layer305, the first portion 306 a, the conductive layers 309 and the part ofthe coil 312 are exposed and brought to the same plane as the surface ofthe insulating layer 314. Through the flattening process, the thicknessof the insulating layer 314 covering the coils 310 and 312 in theconcave 304 is controlled so that the thickness is about 3 μm.

Through the flattening process, the surface of the bottom shield layer305 is made smooth. It is thereby possible to precisely form the MRelement. As a result, the high frequency characteristic of reproducingoutput is improved, for example.

The intermediate product shown in FIG. 75A and FIG. 75B is the thin-filmmagnetic head material of the embodiment. The intermediate productincludes the bottom shield layer 305, the first portion 306 a of the topshield layer, the conductive layers 309 and the thin-film coils 310 and312.

Next, as shown in FIG. 76A and FIG. 76B, an insulating material such asaluminum nitride or alumina is sputtered to tens of nanometers over theentire surface to form a bottom shield gap film 315 a as an insulatinglayer. Before forming the bottom shield gap film 315 a, a photoresistpattern in a T-shape, for example, is formed to facilitate liftoff wherecontact holes are to be formed for electrically connecting theconductive layers 309 to other conductive layers described later. Afterthe bottom shield gap film 315 a is formed, the contact holes are formedthrough lifting off the photoresist pattern. Alternatively, the contactholes may be formed by selectively etching the bottom shield gap film315 a through the use of photolithography.

Next, an MR film of tens of nanometers in thickness for forming an MRelement 316 for reproduction is deposited through sputtering on thebottom shield gap film 315 a. A photoresist pattern (not shown) is thenselectively formed where the MR element 316 is to be formed on the MRfilm. The photoresist pattern may be T-shaped, for example, tofacilitate liftoff. Next, the MR film is etched through argon-base ionmilling, for example, with the photoresist pattern as a mask to form theMR element 316. The MR element 316 may be either a GMR element or an AMRelement.

Next, on the bottom shield gap film 315 a, a pair of conductive layers317 of tens to hundreds of nanometers in thickness are formed throughsputtering with the same photoresist pattern as a mask. The conductivelayers 317 are to be electrically connected to the MR element 316. Theconductive layers 317 may be formed through stacking TiW, CoPt, TiW, Ta,and Au, for example. The conductive layers 317 are electricallyconnected to the conductive layers 309 through the contact holesprovided in the bottom shield gap film 315 a. The conductive layers 317and 309 make up the leads connected to the MR element 316.

Next, an insulating material such as aluminum nitride or alumina issputtered to a thickness of 50 to 100 nanometers to form a top shieldgap film 315 b as an insulating layer. The MR element 316 is thusembedded in the shield gap films 315 a and 315 b. Next, the shield gapfilms 315 a and 315 b are selectively removed through dry etching suchas reactive ion etching using a BCl₃-base gas or a CF₄-base gas with aphotoresist pattern as a mask. A contact hole is thereby formed forconnecting the first portion 306 a to a second portion described laterof the top shield layer. Another contact hole is thereby formed formaking a magnetic path on the insular portion 304 b. Alternatively, thecontact hole for connecting the first portion 306 a to the secondportion of the top shield layer and the contact hole for making themagnetic path may be formed through a liftoff process by formingphotoresist patterns where the contact holes are to be formed, in thestep of forming the shield gap films 315 a and 315 b.

Next, as shown in FIG. 77A and FIG. 77B, a second portion 306 b of thetop shield layer is formed on the side of the pole portion. The secondportion 306 b is made of a magnetic material and has a thickness ofabout 3.5 μm, for example, and is connected to the first portion 306 aof the top shield layer. The second portion 306 b is placed to face thebottom shield layer 305 with the MR element 316 in between. At the sametime, a magnetic layer 318 for making the magnetic path is formed in thecontact hole for making the magnetic path on the insular portion 304 b.The magnetic layer 318 is made of a magnetic material and has athickness of about 3.5 μm. The second portion 306 b of the top shieldlayer and the magnetic layer 318 are formed through plating, forexample.

The bottom shield layer 305 and the top shield layer 306 a and 306 b maybe made of NiFe (80 weight % Ni and 20 weight % Fe) or a high saturationflux density material such as NiFe (50 weight % Ni and 50 weight % Fe),Sendust, FeN or a compound thereof, or an amorphous of Fe—Co—Zr. Thebottom shield layer 305 and the top shield layer 306 a and 306 b may bemade of layers of two or more of those materials. Through the use of ahigh saturation flux density material for the bottom shield layer 305and the top shield layer 306 a and 306 b, it is possible to reduce theeffects of noises on the MR element 316 caused by internal factors suchas magnetism and the like generated by the coil of the induction-typerecording head or external factors such as the motor of the hard diskdrive. A precise reproducing output is therefore achieved and a highlysensitive reproducing head is obtained.

Next, a thin-film coil 319 of a third layer is formed on the bottomshield gap film 315 a on the coils 310 and 312. The coil 319 may be madeof copper through plating with a photoresist film as a mask.Alternatively, the coil 319 may be formed through sputtering.

Next, in the second portion 306 b of the top shield layer, a step 320 isformed by etching a portion behind the point defining the throat height(that is, a portion far from the air bearing surface) by about 0.5 to 3μm. In the embodiment the throat height is defined by the edge of thestep 320 closer to the air bearing surface.

Next, as shown in FIG. 78A and FIG. 78B, an insulating layer 321 ofalumina or silicon dioxide, for example, whose thickness is about 3 to 4μm is formed on the entire surface. The insulating layer 321 is thenpolished to the surfaces of the second portion 306 b of the top shieldlayer, the conductive layers 318 and part (not shown) of the coil 319and flattened. The polishing method may be mechanical polishing or CMP.Through this flattening process, the surfaces of the second portion 306b, the conductive layers 318 and the part of the coil 319 are exposedand brought to the same plane as the surface of the insulating layer321.

Next, a recording gap layer 322 of about 150 to 250 nm in thickness madeof an insulating film of alumina, aluminum nitride, or silicon dioxide,for example, is formed on the entire surface. The recording gap layer322 on the magnetic layer 318 is then partially etched to form a contacthole for making the magnetic path.

Next, as shown in FIG. 79A and FIG. 79B, a top pole layer 323 of about 3μm in thickness is formed on the recording gap layer 322. The top polelayer 323 determines the track width of the induction recording head.The top pole layer 323 may be formed through plating with NiFe (50weight % Ni and 50 weight % Fe), or through sputtering a high saturationflux density material such as FeN or a compound thereof and thenpatterning. Besides the above examples, the material of the top polelayer 323 may be NiFe (80 weight % Ni and 20 weight % Fe) or a highsaturation flux density material such as an amorphous of Fe—Co—Zr.Alternatively, the top pole layer 323 may be layers of two or more ofthe above materials. The top pole layer 323 made of a high saturationflux density material allows the magnetic flux generated by the coils310, 312 and 319 to effectively reach the pole portion withoutsaturating before reaching there. An efficient recording head istherefore obtained.

Next, as shown in FIG. 80A and FIG. 80B, part of the recording gap layer322 on both sides of the top pole layer 323 is removed through dryetching such as reactive ion etching. The exposed second portion 306 bof the top shield layer is then etched through ion beam etching such asion milling with the top pole layer 323 as a mask to form a trimstructure.

Next, an overcoat layer 324 of alumina, for example, whose thickness isabout 3 to 5 μm is formed to cover the top pole layer 323. Next, on theovercoat layer 324 a plurality of pads are formed to allow connectionbetween the electrodes of the reproducing head and the recording headand the outside. In prior-art techniques the thickness of the overcoatlayer made of alumina, for example, is as thick as 30 to 40 μm andcolumnar electrodes (bumps) connected to the reproducing head andcolumnar electrodes connected to the recording head are formed to beembedded in the overcoat layer. The surface of the thick overcoat layeris polished for a long time to expose the electrodes from the overcoatlayer surface and the pads are thus formed. In the embodiment, incontrast, since the overcoat layer 324 is thin, it is possible to etchthe overcoat layer 324 through dry etching such as ion milling orreactive ion etching. The electrodes embedded in the overcoat layer 324are thereby exposed from the surface of the overcoat layer 324 to formthe pads.

Finally, machine processing of the slider is performed and the airbearing surface of the recording head and the reproducing head isformed. The thin-film magnetic head is thus completed.

The top shield layer (bottom pole layer) 306 a and 306 b, the magneticlayer 318, the top pole layer 323, and the thin-film coils 310, 312 and319 correspond to a recording head of the invention. That is, the topshield layer (bottom pole layer) 306 a and 306 b and the magnetic layer318 correspond to a first magnetic layer of the recording head of theinvention. The top pole layer 323 corresponds to a second magneticlayer.

FIG. 81 is a top view of the thin-film magnetic head of the embodimentmanufactured through the foregoing process in the state in one of themanufacturing steps. FIG. 82 is a top view of the thin-film magnetichead of the embodiment manufactured through the foregoing process. FIG.81 corresponds to the state shown in FIG. 75A and FIG. 75B. In FIG. 82the overcoat layer 324 is omitted. FIG. 82 shows the state beforemechanical processing of the slider is performed. Numeral 325 of FIG. 82indicates the contact hole for connecting the second portion 306 b tothe first portion 306 a of the top shield layer. Numeral 326 of FIG. 81and FIG. 82 indicates the edge of the concave 304. FIG. 69A to FIG. 80Aare cross sections taken along line 80A—80A of FIG. 82. FIG. 69B to FIG.80B are cross sections taken along line 80B—80B of FIG. 82.

In this embodiment, as shown in FIG. 82, shield layers 327 may beprovided for shielding at least portions of the conductive layers 309.The shield layers 327 cover the portions of the conductive layers 309that do not face the second portion 306 b of the top shield layer. Inthe step of forming the top pole layer 323, for example, the shieldlayers 327 may be made of the same material as the top pole layer 323 atthe same time.

In the embodiment the bottom shield layer 305 and the first portion 306a of the top shield layer do not overlap each other while insulated fromeach other. The portions of the conductive layers 309 making up theleads connected to the MR element 316 are placed in the grooves 307provided between the bottom shield layer 305 and the first portion 306a, being insulated by the insulating film 308 from the bottom shieldlayer 305 and the first portion 306 a.

As described above, many customers of thin-film magnetic heads order thetrack width of a reproducing head and the throat height and the trackwidth of a recording head that suit their own products. However, ifthin-film magnetic heads that meet the specifications a customerrequires are manufactured after an order is received, it is difficult tosupply the products in a short time after the receipt of the order.

According to the embodiment, as shown in FIG. 75A and FIG. 75B, thethin-film magnetic head material commonly used for thin-film magneticheads is completed in the step of forming part of the thin-film coils,that is, the coil 310 of the first layer and the coil 312 of the secondlayer in the concave 304 of the insulating layer 302 and forming theinsulating layer 314. It takes a relatively short time to perform thesteps that follow the formation of the thin-film magnetic head material.In addition, it is possible to inspect the thin-film magnetic headmaterials and remove nonconforming ones.

Therefore, according to the embodiment, the intermediate product, thatis, the thin-film magnetic head material, having gone through themanufacturing steps as far as the step of forming the coils 310 and 312may be mass-produced so that many intermediate products in stock areobtained. Such intermediate products in stock may be increased so thatthey are plentiful enough to be supplied to customers. Thespecifications of the thin-film magnetic heads may be then determined tomeet different customers' demands. Therefore, the embodiment allows theappropriate number of intermediate products in stock to be obtained.Such intermediate products have gone through 50 to 60 percent of theentire manufacturing steps and many of them have passed an inspection asconforming products. It is therefore possible to produce thin-filmmagnetic heads that meet the specifications required by the customer ina short time after receipt of an order. As a result, the cycle time froma receipt of a customer's order to a completion and a shipment ofthin-film magnetic heads may be two weeks or less, according to theembodiment, which is shorter than twenty to forty days required inprior-art methods.

According to the embodiment, noncorfoming intermediate products havebeen already eliminated so that it is possible to make conforming ii Iintermediate products into complete products as soon as possible inaccordance with customers' demands. High quality of the products that isnot obtained by prior-art techniques is therefore achieved and theyields of the finished products improve.

According to the embodiment, it is possible to meet the customer'sdemand immediately even if it is changed in a short time. It istherefore possible to prevent products from being wasted.

According to the embodiment, intermediate products may be inspected sothat the manufacturing steps that follow do not need to be performed onnonconforming products. As a result, manufacturing costs of thethin-film magnetic heads are reduced, compared to prior art.

According to the embodiment, inspections may be performed on bothintermediate products and completed thin-film magnetic heads. Extremelyhigh quality products are thereby assured.

According to the embodiment, inspections may be performed on bothintermediate products and completed thin-film magnetic heads. As aresult, it is easy to detect a manufacturing step with a problem and toimmediately improve such a step. It is thereby possible to prevent amore serious problem.

According to the embodiment, the conductive layers 309 and the thin-filmcoil 310 of the first layer or the thin-film coil 312 of the secondlayer are formed at the same time. As a result, it is possible to reducethe number of manufacturing steps of the thin-film magnetic head or thethin-film magnetic head material.

According to the embodiment, the bottom shield layer 305 and the firstportion 306 a of the top shield layer are formed at the same time. As aresult, it is possible to further reduce the number of manufacturingsteps of the thin-film magnetic head or the thin-film magnetic headmaterial.

According to the embodiment, the MR element 316 is formed after thecoils 310 and 312 are formed. It is therefore possible to prevent areduction in the property of the MR element 316 due to the influence ofheat treatment performed on the photoresist when the coils 310 and 312are formed and the influence of water thereby generated and so on. Thispreventing effect is particularly effective when the MR element 316 is asensitive GMR element. In the embodiment the thin-film coil 319 isformed after the MR element 316 is formed. Covering the coil 319 withthe insulating layer 321 of alumina or silicon dioxide, for example,prevents a reduction in the property of the MR element 316 due to theinfluence of heat treatment performed on the photoresist and theinfluence of water thereby generated and so on.

According to the embodiment, the number of manufacturing steps thatfollow the formation of the MR element 316 is reduced, compared toprior-art methods. It is therefore possible to greatly reduce breakagesuch as static damage of the MR element 316 caused by handling and soon. This effect is particularly effective when the MR element 316 is aGMR element made of layers of a plurality of extremely thin (about 1 to5 nm) films.

In the embodiment the first portion 306 a of the top shield layer doesnot overlap the portion of the bottom shield layer 305 where the MRelement 316 is placed, being insulated from the bottom shield layer 305.The portions of the conductive layers 309 making up the leads connectedto the MR element 316 are placed in the grooves 307 provided between thebottom shield layer 305 and the first portion 306 a, being insulated bythe insulating film 308 from the bottom shield layer 305 and the firstportion 306 a. As a result, according to the embodiment, an extremelyhigh insulation property is achieved between the conductive layers 309and the bottom shield layer 305 and the first portion 306 a of the topshield layer. Although part of the conductive layers 309 faces thesecond portion 306 b of the top shield layer with the bottom shield gapfilm 315 a and the top shield gap film 315 b in between, the most partof the conductive layers 309 does not face the top shield layer 306 aand 306 b. An extremely high insulation property is therefore achievedbetween the conductive layers 309 and the top shield layer 306 a and 306b.

According to the embodiment, an extremely high insulation property isachieved between the conductive layers 309 and the bottom shield layer305 and the top shield layer 306 a and 306 b. It is therefore possibleto prevent magnetic and electrical insulation faults between theconductive layers 309 and the bottom shield layer 305 and the top shieldlayer 306 a and 306 b.

According to the embodiment, the conductive layers 309 are not insertedbetween the bottom shield gap film 315 a and the top shield gap film 315b. As a result, it is impossible that large areas of the conductionlayers 309 face the bottom shield layer 305 and the top shield layer 306a and 306 b with the bottom shield gap film 315 a and the top shield gapfilm 315 b in between. Therefore, although the bottom shield gap film315 a and the top shield gap film 315 b are thin, the insulationproperty is maintained at a high level between the conductive layers 309and the bottom shield layer 305 and between the conductive layers 309and the top shield layer 306 a and 306 b.

According to the embodiment described so far, the insulation property isimproved between the conductive layers connected to the MR element 316and the bottom shield layer 305 and between the conductive layers andthe top shield layer 306 a and 306 b without increasing the thickness ofthe bottom shield gap film 315 a and the top shield gap film 315 b.

According to the embodiment, the bottom shield gap film 315 a and thetop shield gap film 315 b are made thin enough to improve the thermalasperity. The property of the reproducing head is thereby improved.

According to the embodiment, the conductive layers 309 are made thickenough so that the wiring resistance of the conductive layers connectedto the MR element 316 is more greatly reduced. As a result, it ispossible to detect with sensitivity a minute change in the output signalcorresponding to a minute change in resistance of the MR element 316.The property of the reproducing head is improved in this respect, too.

In the embodiment, the lateral surfaces of the portions of theconductive layers 309 close to the MR element 316 and placed in thegrooves 307 are shielded, being placed between the bottom shield layer305 and the first portion 306 a of the top shield layer. The topsurfaces of the portions of the conductive layers 309 are shielded bythe second portion 306 b of the top shield layer. As a result, it ispossible to reduce the effects of noises caused by internal factors suchas magnetism and the like generated by the coil of the induction-typerecording head or external factors such as the motor of the hard diskdrive. The property of the reproducing head is improved in this respect,too.

Since the shield layers 327 for the conductive layers are provided, itis possible to shield the top surfaces of the portions of the conductivelayers 309 not facing the second portion 306 b of the top shield layer.The effects of noises on the conductive layers 309 are thereby furtherreduced.

According to the embodiment, part of the thin-film coils, that is, thethin-film coils 310 and 312 are placed in the concave 304 formed in thebase body. As a result, the height of the apex, that is, the crest ofthe coil is reduced and the pole layer (the top pole layer 323) thatdefines the track width of the recording head is reduced in size. Therecording density is thereby increased and the recording head propertyis improved. According to the embodiment, the apex will not be increasedin size even if the thin-film coils are made up of two or three layersto improve the recording head property. Therefore, it is possible toreduce the size of the pole layer (the top pole layer 323) that definesthe track width of the recording head while increasing the layers of thethin-film coils and to improve the recording head property. It is thuspossible to form the four-layer thin-film coils, for example. Ahigher-performance recording head is thereby implemented.

According to the embodiment, the flattening process is performed so thatthe surfaces of the second portion 306 b of the top shield layer, themagnetic layer 318 and the insulating layer 321 are brought to oneplane. On the flattened surfaces the top pole layer 323 is formed withthe recording gap layer 322 in between. As a result, the top pole layer323 that defines the track width of the recording head is reduced insize and the recording head property is improved.

According to the embodiment, the top pole layer of the recording head isnot made up of two layers including a top pole tip and a top yoke layerbut made up of a single layer of the top pole layer 323. It is thereforeimpossible that the top yoke layer greater than the top pole tip inwidth is exposed in the air bearing surface. As a result, it is possibleto prevent problems such as an increase in effective track width andwriting data in a region other than the region where data is to bewritten on a recording medium.

According to the embodiment, there is no possibility of magnetic fluxsaturation that is generated in a contact portion between the top poletip and the top yoke layer when the top pole layer is made up of twolayers including the top pole tip and the top yoke layer. The writingproperties such as magnetic flux rise time is therefore improved.

In prior art an overcoat layer of alumina, for example, whose thicknessis about 30 to 40 μm is formed to protect the reproducing head and therecording head and to maintain the quality of the product in a stepimmediately before the completion of the mass-production process of thethin-film magnetic heads. Consequently, warpage of the substrate resultsdue to the thick overcoat layer or many particles are generated when thethick layer is formed through sputtering. The property and yields of thethin-film magnetic heads are thereby reduced. In prior art it takesfifteen hours or more to form the alumina film of about 40 μm inthickness by sputtering. The cycle time of mass-production of thethin-film magnetic heads and the sputtering capability are thereforegreatly limited.

In the embodiment, in contrast, the thin-film coils 310 and 312 areprovided in the concave 304 so that the surface of the top pole layer323 below the overcoat layer 324 is almost flat. As a result, theovercoat layer 324 is made thin. Since the overcoat layer 324 is thin inthe embodiment, the electrodes embedded in the overcoat layer 324 areexposed from the surface of the overcoat layer 324 by etching theovercoat layer 324 through dry etching such as ion milling or reactiveion etching. The pads are thereby formed. As a result, according to theembodiment, the process time for forming the overcoat layer 324 and theprocess time for forming the pads are greatly reduced (that is, reducedto a tenth, for example), compared to prior-art methods. The cycle timeof mass-production of the thin-film magnetic heads is reduced as well.

According to the embodiment, there is no possibility of warpage of thesubstrate due to the thick overcoat layer or many particles generatedwhen the thick layer is formed through sputtering. The property andyields of the thin-film magnetic heads are therefore maintained.

In the embodiment, the insulating layer 302 made of alumina is formed onthe substrate 301 made of aluminum oxide and titanium carbide(Al₂O₃-TiC). The concave 304 is then formed in the insulating layer 302on which the bottom shield layer 305 and the first portion 306 a of thetop shield layer are formed. Alternatively, the following configurationmay be possible. A concave is formed in a ceramic substrate made up ofan alumina layer and an aluminum oxide and titanium carbide layerstacked thereon. An insulating layer of alumina is then formed on thesubstrate having the concave on which the bottom shield layer 305 andthe first portion 306 a of the top shield layer are formed. Anotheralternative is that a metal mask of a specific pattern is formed byplating directly on a substrate made of aluminum oxide and titaniumcarbide or on a thin alumina layer formed on the substrate. A concave isformed by etching the substrate through dry etching, for example, withthe metal mask. On the substrate having the concave an insulating layerof alumina is formed on which the bottom shield layer 305 and the firstportion 306 a of the top shield layer are formed.

[Twentieth Embodiment]

Reference is now made to FIG. 83A and FIG. 83B to describe a twentiethembodiment of the invention. FIG. 83A is a cross section of a thin-filmmagnetic head of the embodiment orthogonal to the air bearing surface.FIG. 83B is a cross section of the pole portion of the thin-filmmagnetic head parallel to the air bearing surface. FIG. 83A shows thestate before mechanical processing of the slider is performed.

In the embodiment, in the top surface of the substrate 301 made ofaluminum oxide and titanium carbide (Al₂O₃-TiC), a concave 331 similarto the concave 304 of the nineteenth embodiment is formed. Next, aninsulating film 332 of alumina, for example, whose thickness is about0.5 to 1 μm is formed by sputtering, for example, on the entire surface.Next, on the insulating film 332 the bottom shield layer 305 and thefirst portion 306 a of the top shield layer similar to those of thenineteenth embodiment are formed at the same time in one manufacturingstep. The steps performed until the formation of the insulating layer314 are similar to those of the nineteenth embodiment. Upon theformation of the insulating layer 314, the thin-film magnetic headmaterial commonly used in thin-film magnetic heads is completed as inthe nineteenth embodiment.

In this embodiment, in order to complete the product to meet thecustomer's demands, the MR element (an AMR element or a GMR element, andso on) and the material of the shield gap films (alumina, aluminumnitride or boron nitride and so on) are selected and the track width ofthe reproducing head and the throat height and the track width of therecording head are determined in accordance with the customer'srequests. As in the nineteenth embodiment, the bottom shield gap film315 a, the MR element 316, the conductive layers 317 and the top shieldgap film 315 b are then formed. The numerals of these components areomitted in FIG. 83A and FIG. 83B.

In the embodiment, as in the nineteenth embodiment, the second portion306 b of the top shield layer and the magnetic layer 318 are thenformed. Next, on the bottom shield gap film 315 a above the coils 310and 312, the insulating layer 321 of alumina or silicon dioxide, forexample, having a thickness of 3 to 4 μm is formed over the entiresurface instead of forming the thin-film coil 319. Next, as in thenineteenth embodiment, the insulating layer 321 is polished to thesurfaces of the second portion 306 b, the magnetic layer 318 and part(not shown) of the coil 319 and flattened.

Next, on the insulating layer 321, an insulating layer 333 ofphotoresist that defines the throat height is formed. Next, a recordinggap layer 334 made of an insulating film of alumina, aluminum nitride,or silicon dioxide is formed over the entire surface. The portion of therecording gap layer 334 on the magnetic layer 318 is then selectivelyremoved to form a contact hole for making a magnetic path.

Next, a top pole layer 335 is formed on the recording gap layer 344. Thetop pole layer 335 defines the track width of the recording head. Next,the recording gap layer 334 on sides of the top pole layer 335 isremoved through dry etching such as reactive ion etching. The exposedsecond portion 306 b of the top shield layer is etched through ion beametching such as ion milling with the top pole layer 335 as a mask. Atrim structure is thereby formed.

Next, an overcoat layer 336 of alumina, for example, whose thickness isabout 3 to 5 μm is formed to cover the top pole layer 335. Next, aplurality of pads are formed on the overcoat layer 336. Finally, machineprocessing of the slider is performed and the air bearing surface of therecording head and the reproducing head is formed. The thin-filmmagnetic head is thus completed.

The remainder of configuration, functions and effects of the embodimentare similar to those of the nineteenth embodiment.

[Twenty-first Embodiment]

Reference is now made to FIG. 84 and FIG. 85 to describe a twenty-firstembodiment of the invention. FIG. 84 is a top view of a thin-filmmagnetic head fabricated through the manufacturing method of theembodiment in the state in one of the manufacturing steps. FIG. 85 is atop view of the thin-film magnetic head fabricated through themanufacturing method of the embodiment Compared to the nineteenthembodiment, the first portion 306 a of the top shield layer is smallerin this embodiment. That is, the first portion 306 a of the embodimentextends from the neighborhood of the pole-portion-side edge of theconcave of the substrate outside the concave to the neighborhood of theinsular portion. Since the top shield layer functions as the bottom polelayer of the recording head as well, the small first portion 306 a ofthe top shield layer of the embodiment has an advantage for being usedin a thin-film magnetic head capable of high-frequency operation.

The remainder of configuration, functions and effects of the embodimentare similar to those of the nineteenth embodiment.

[Twenty-second Embodiment]

Reference is now made to FIG. 86 to describe a twenty-second embodimentof the invention. FIG. 86 is a top view of the thin-film magnetic headfabricated through the manufacturing method of the embodiment in thestate in one of the manufacturing steps.

As in the twenty-first embodiment, the first portion 306 a of the topshield layer is smaller in this embodiment, compared to the nineteenthembodiment. Furthermore, the bottom shield layer 305 is smaller as wellin this embodiment, compared to the nineteenth embodiment. That is, thebottom shield layer 305 is formed only in the region near the MRelement.

In the embodiment magnetic layers 341 are formed to hold lateralsurfaces of the most part of the portions of the conductive layers 309not placed between the bottom shield layer 305 and the first portion 306a of the top shield layer. The magnetic layers 341 are placed outsidethe concave 304 on the insulating layer 302 shown in FIG. 70A and FIG.70B. The magnetic layers 341 are insulated from the top shield layer 305and the first portion 306 a without overlapping them. In the step offorming the bottom shield layer 305 and the first portion 306 a of thetop shield layer, the magnetic layers 341 are made of the same materialat the same time.

In the embodiment, although not shown, the shield layers 327 areprovided for covering the portions of the conductive layers 309 notfacing the second portion 306 b of the top shield layer as in thenineteenth embodiment.

According to the embodiment, the lateral surfaces of the conductivelayers 309 are shielded by the magnetic layers 341 and the top surfacesof the conductive layers 309 are shielded by the shield layers 327. As aresult, the effects of noises are further reduced.

The remainder of configuration, functions and effects of the embodimentare similar to those of the twenty-first embodiment.

[Twenty-third Embodiment]

Reference is now made to FIG. 87A, FIG. 87B, FIG. 88A and FIG. 88B todescribe a composite thin-film magnetic head and a method ofmanufacturing the same of a twenty-third embodiment of the invention.FIG. 87A and FIG. 88A are cross sections each orthogonal to the airbearing surface of the thin-film magnetic head. FIG. 87B and FIG. 88Bare cross sections each parallel to the air bearing surface of the poleportion of the head.

The thin-film magnetic head of the embodiment is similar to that of thesixteenth embodiment except that the insulating film 256 is provided inplace of the insulating layer 258 placed below the coil 259. In themethod of manufacturing the thin-film magnetic head of the embodiment,the steps taken to reach the state shown in FIG. 56A and FIG. 56B aresimilar to those of the sixteenth embodiment. In the next step of theembodiment, as shown in FIG. 87A and FIG. 87B, the coil 259 is formed onthe insulating film 256 and the conductive layers 257 are formed in thegrooves 255 covered with the insulating film 256, the coil 259 and theconductive layers 257 being made of the same material. Next, theinsulating layer 260 of photoresist is formed into a specific pattern onthe insulating film 256 and the coil 259. The insulating film 256 isthen patterned with the insulating layer 260 as a mask.

The thin-film magnetic head material of the embodiment is theintermediate product shown in FIG. 87A and FIG. 87B, that is, the onecomprising the bottom shield layer 253, the first portion 254 a of thetop shield layer, the conductive layers 257 and the thin-film coil 259.The top view of the intermediate product shown in FIG. 87A and FIG. 87Bis similar to the one shown in FIG. 61 as in the sixteenth embodiment.

The manufacturing steps of the embodiment taken to process theintermediate product shown in FIG. 87A and FIG. 87B into the thin-filmmagnetic head shown in FIG. 88A and FIG. 88B are similar to the stepsshown in FIG. 58A to FIG. 60A and FIG. 58B to FIG. 60B of the sixteenthembodiment. The top view of the thin-film magnetic head of theembodiment is similar to the one shown in FIG. 62 as in the sixteenthembodiment.

In the embodiment the shield layers 271 for shielding at least part ofthe conductive layers 257 may be provided as shown in FIG. 62 as in thesixteenth embodiment.

According to the embodiment, the number of the manufacturing steps aregreatly reduced, compared to the sixteenth embodiment.

The remainder of configuration, functions and effects of the embodimentare similar to those of the sixteenth or nineteenth embodiment.

[Twenty-fourth Embodiment]

Reference is now made to FIG. 89A and FIG. 89B to describe atwenty-fourth embodiment of the invention. FIG. 89A is a cross sectionorthogonal to the air bearing surface of a thin-film magnetic head. FIG.89B is a cross section parallel to the air bearing surface of the poleportion of the head. FIG. 89A shows the state before mechanicalprocessing of the slider is performed.

In the thin-film magnetic head of the embodiment, the thin-film coil 272of the second layer is formed in the insulating layer 265 made ofphotoresist of the thin-film magnetic head of the twenty-thirdembodiment. In this case, the insulating layer 265 of photoresist havinga specific thickness is formed over the coil 259. The coil 272 is thenformed through plating, for example. The insulating layer 265 is furtherformed to cover the coil 272. The throat height is defined by theinsulating layer 265 in this embodiment.

The remainder of configuration, functions and effects of the embodimentare similar to those of the twenty-third embodiment.

[Twenty-fifth Embodiment]

Reference is now made to FIG. 90A and FIG. 90B to describe atwenty-fifth embodiment of the invention. FIG. 90A is a cross sectionorthogonal to the air bearing surface of the thin-film magnetic head.FIG. 90B is a cross section parallel to the air bearing surface of thepole portion of the head. FIG. 90A shows the state before mechanicalprocessing of the slider is performed.

The thin-film magnetic head of the embodiment is similar to that of theeighteenth embodiment except that the insulating film 256 is provided inplace of the insulating layer 258 placed below the coil 259. In themethod of manufacturing the thin-film magnetic head of the twenty-fifthembodiment, the steps taken to reach the step of forming the coil 259shown in FIG. 87A and FIG. 87B are similar to those of the twenty-thirdembodiment. The intermediate products having gone through the steps aremass-produced and inspected. An appropriate amount of conformingintermediate products are obtained. The top view of the intermediateproduct of the embodiment is similar to the one shown in FIG. 67 as inthe eighteenth embodiment.

The manufacturing steps of the embodiment taken to process theintermediate product shown in FIG. 87A and FIG. 87B into the thin-filmmagnetic head shown in FIG. 90A and FIG. 90B are similar to those shownin FIG. 64A to FIG. 66A and FIG. 64B to FIG. 66B of the eighteenthembodiment. The top view of the thin-film magnetic head of thetwenty-fifth embodiment is similar to the one shown in FIG. 68 as in theeighteenth embodiment.

In the twenty-fifth embodiment the shield layers 271 for shielding atleast part of the conductive layers 257 may be provided as shown in FIG.68 as in the twenty-third embodiment. The shield layers 271 is formed tocover the portions of the conductive layers 257 not facing the secondportion 254 b of the top shield layer. In the step of forming the toppole layer 286, for example, the shield layers 271 are made of the samemagnetic material as the top pole layer 286 at the same time.

The remainder of configuration, functions and effects of the embodimentare similar to those of the eighteenth or twenty-third embodiment.

In the nineteenth to twenty-fifth embodiment the thin-film magnetic headmaterial is manufactured that comprises the first shield layer, thefirst portion of the second shield layer, at least part of theconductive layers to be connected to the MR element, and at least partof the thin-film coils. In response to the customer's requests, thesecond portion of the second shield layer, the MR element, and thesecond magnetic layer are added to the material. The thin-film magnetichead is thus manufactured. As a result, according to the embodiments, itis possible to provide thin-film magnetic heads that meet thespecifications required by the customer in a short period of time.According to the embodiments, the materials are inspected so that it ispossible to process only conforming materials into thin-film magneticheads. The yields of the heads are thereby improved. According to theembodiments, it is possible to fabricate at least part of the conductivelayers to be connected to the MR element and at least part of thethin-film coils at the same time. As a result, it is possible to reducethe number of manufacturing steps of the thin-film magnetic head or thethin-film magnetic head material.

It is possible to further reduce the number of manufacturing steps ofthe thin-film magnetic head or the thin-film magnetic head material ifthe first shield layer and the first portion of the second shield layerare formed at the same time in one step.

In the step of forming at least part of the conductive layers and atleast part of the thin-film coils at the same time, the part of theconductive layers may be formed to be placed between the first shieldlayer and the first portion of the second shield layer, being insulatedfrom them. In this case the following effects are achieved. A highinsulation property is achieved between the conductive layers and eachshield layer. In addition, since the conductive layers are not placedbetween the shield layers with insulating layers in between, theinsulation property is improved between each shield layer and theconductive layers connected to the MR element without increasing thethickness of the insulating layer between the MR element and the shieldlayer. In this case, it is possible to fabricate the conductive layerssufficiently thick. The wiring resistance of the conductive layers isthereby reduced. Furthermore, the portions of the conductive layersplaced between the first shield layer and the first portion of thesecond shield layer are shielded, being placed between the two shieldlayers. The effects of noises on the conductive layers are therebyreduced.

In the step of forming the first shield layer and the first portion ofthe second shield layer, the first shield layer and the first portionmay be formed such that, on the base body having the concave, at leastpart of the first shield layer is placed in a portion other than theconcave, part of the first portion is placed in a portion other than theconcave, and the remaining part of the first portion is placed along theinner surface of the concave. In addition, in the step of forming atleast part of the conductive layers and at least part of the thin-filmcoils at the same time, the part of the thin-film coil may be placed inthe concave. In such a case, the following effects are achieved. Theheight of the crest of the coil is reduced and the second magnetic layerthat defines the track width of the recording head is greatly reduced insize.

At least part of the thin-film coil may be placed in the concave, andthe insulating layer may be then formed to cover the part of thethin-film coil and the surfaces of the insulating layer, the firstshield layer and the first portion of the second shield layer may beflattened so that the surfaces are brought to one plane. In this case itis possible to precisely fabricate the MR element.

The second magnetic layer that defines the track width of the recordinghead is greatly reduced in size if the following steps are taken. Thatis, part of the thin-film coil is placed in the concave, and the firstinsulating layer is then formed to cover the part of the thin-film coil.The second insulating layer is then formed to cover the remaining partof the thin-film coil. The surfaces of the second insulating layer andthe second portion of the top shield layer are flattened so that thesurfaces are brought to one plane.

If the shield layers are provided for shielding at least part of theconductive layers, the effects of noises on the conductive layers arefurther reduced.

The present invention is not limited to the foregoing embodiments. Forexample, in the first to thirteenth embodiments, the top pole layer ofthe recording head is made up of the two layers of the top pole tip andthe top yoke layer. Alternatively, the top pole layer may be made of asingle layer in those embodiments. In the fourteenth to twenty-fifthembodiments, the top pole layer is made of the single layer.Alternatively, the top pole layer may be made of the two layers of thetop pole tip and the top yoke layer in those embodiments.

In the foregoing embodiments the thin-film magnetic head is disclosed,comprising the MR element for reading formed on the base body and theinduction-type magnetic transducer for writing stacked on the MRelement. Alternatively, the MR element may be stacked on the magnetictransducer.

That is, the induction-type magnetic transducer for writing may beformed on the base body and the MR element for reading may be stacked onthe transducer. Such a structure may be achieved by forming a magneticfilm functioning as the top pole layer of the foregoing embodiments as abottom pole layer on the base body, and forming a magnetic filmfunctioning as the bottom pole layer of the embodiments as a top polelayer facing the bottom pole layer with a recording gap film in between.In this case it is preferred that the top pole layer of theinduction-type magnetic transducer functions as the bottom shield layerof the MR element as well.

In the thin-film magnetic head having such a structure, the top shieldlayer provided for the MR element corresponds to the first shield layerof the invention. Therefore, in the thin-film magnetic head the groovesin which the conductive layers are placed may be formed in the topshield layer.

A base body having a concave is preferred for the thin-film magnetichead having such a structure. If the coils are formed in the concave ofthe base body, the thin-film magnetic is further reduced in size.

Alternatively, the insulating layers formed between the thin-film coilsforming the coils of the induction-type magnetic transducer may be allmade of inorganic layers.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed is:
 1. A thin-film magnetic head comprising: areproducing head including: a magnetoresistive element; a first shieldlayer and a second shield layer for shielding the magnetoresistiveelement, portions of the first shield layer and the second shield layerthat face a recording medium being opposed to each other with themagnetoresistive element in between; a first insulating layer providedbetween the magnetoresistive element and the first shield layer and asecond insulating layer provided between the magnetoresistive elementand the second shield layer; and a recording head including: a firstmagnetic layer and a second magnetic layer magnetically coupled to eachother and each made up of at least one layer and including magnetic poleportions opposed to each other and each located in a respective endregion of the magnetic layers that faces toward a recording medium; agap layer placed between the pole portions of the first and secondmagnetic layers; and a thin-film coil at least part of which is placedbetween the first and second magnetic layers and insulated from thefirst and second magnetic layers; wherein: the second shield layerincludes a first portion placed in a plane the same as a plane in whichthe first shield layer is placed, the first portion being insulated fromthe first shield layer by an insulating film, and a second portionconnected to the first portion and opposed to the first shield layerwith the magnetoresistive element in between, the first portion and thesecond portion being separate from each other; and the second shieldlayer also functions as the first magnetic layer; and the at least partof the thin-film coil is placed between the first portion of the secondshield layer and the second magnetic layer.
 2. The thin-film magnetichead according to claim 1, further comprising a conductive layerconnected to the magnetoresistive element, wherein at least part of theconductive layer is placed between the first shield layer and the firstportion of the second shield layer, the conductive layer being insulatedfrom the first shield layer and the first portion by the insulatingfilm.
 3. The thin-film magnetic head according to claim 2, furthercomprising a shield layer for shielding the at least part of theconductive layer.
 4. A thin-film magnetic head sub-structure used formanufacturing a thin-film magnetic head that comprises: a reproducinghead including: a magnetoresistive element; a first shield layer and asecond shield layer for shielding the magnetoresistive element, portionsof the first shield layer and the second shield layer that face arecording medium being opposed to each other with the magnetoresistiveelement in between; a first insulating layer provided between themagnetoresistive element and the first shield layer and a secondinsulating layer provided between the magnetoresistive element and thesecond shield layer; and a recording head including: a first magneticlayer and a second magnetic layer magnetically coupled to each other andeach made up of at least one layer and including magnetic pole portionsopposed to each other and each located in a respective end region of themagnetic layers that faces toward a recording medium; a gap layer placedbetween the pole portions of the first and second magnetic layers; and athin-film coil at least part of which is placed between the first andsecond magnetic layers and insulated from the first and second magneticlayers; wherein: the second shield layer includes a first portion placedin a plane the same as a plane in which the first shield layer isplaced, the first portion being insulated from the first shield layer byan insulating film, and a second portion connected to the first portionand opposed to the first shield layer with the magnetoresistive elementin between, the first portion and the second portion being separate fromeach other; and the second shield layer also functions as the firstmagnetic layer; the thin-film magnetic head sub-structure comprising:the first shield layer; the first portion of the second shield layerplaced in the same plane as the first shield layer, the first portionbeing insulated from the first shield layer by an insulating film, andat least part of the thin-film coil placed on the first portion of thesecond shield layer, the at least part of the thin-film coil beinginsulated from the first portion by an insulating layer.
 5. Thethin-film magnetic head sub-structure according to claim 4, furthercomprising at least part of a conductive layer to be connected to themagnetoresistive element, wherein the at least part of the conductivelayer is placed between the first shield layer and the first portion ofthe second shield layer, the conductive layer being insulated from thefirst shield layer and the first portion by the insulating film.